One of the thing that is so incredibly irritating about working on a college campus is that the female students are almost always referred to as girls while the males are almost always referred to as men. This is almost universal among faculty and staff. Oh, except for the ancient male faculty members who insist on referring to the girls as "co-eds." Don't even get me started on that one.

I see "girl" as a social term and "woman" as a term to be used in the professional world or in any other sort of impersonal institution. The legal definition of adulthood (18) is useful in some cases, not so much in other cases. I work with an all-male office (except for me obviously) and they have always referred to me as a woman (I am 24, for reference). However, when discussing bars or anything social they talk about "girls" there (and I often say "guys," which I find a more natural compliment to girls than "boys").

I think if you see yourself as a woman and someone at work or school is calling you a girl (especially someone who does not know you well), it's a problem. If your boyfriend is calling you "my girl" or you are calling up your "girlfriends," I don't really see the issue. The sexual implications of being called a "girl" or "woman" is that one highlights youth/beauty and the other one maturity/wisdom. It is problematic that men don't have a similar dichotomy (i.e. a man would NEVER want to be called a boy but a woman may like to be called a girl), but that sort of stems back to the entire culture and not the words themselves.

I see it as a maturity thing.
I consider myself a young woman, because I am young, but I'm not a girl. If females are acting immature for their age at this point (I'm 17) I'd consider them girls.
It's more thought-out in my head.

Girl is up to 17 and woman is 18 and up.

I consider the term womyn to refer to any aged female who is acting mature and strong. The more autonomous spelling indicates that it is designated for those females that are displaying considerable intelligence and stregth regardless of age. Little Womyn!

Could language be a factor? In Hindi, there is a female equivalent of "guy", which does get used -- though definitely less often than the "girl" equivalent. Still it's nice to have the option. Can anyone else report on any of the other languages?

When it comes to English, I go by what Gopher mentioned earlier -- below/above 18.

This is why so many people try to use the term "young woman" in cases where overlap may be appropriate. But that isn't always possible ("A 15 year old young woman" for example would be a disastrous phrase).

I've never been a fan of forcing people to emphasize or belittle someones maturity level in their one word identifier. We generally only do this with gender. This is a terrible problem in men's psychology too because "Be a man" and "separating the men from the boys" have become such ubiquitous methods of enforcing the patriarchy.

The two elements can't really be separated. When the hypothetical 16-year old is working to pay her mom's medical bills AND to buy her pink prom dress, she is being both a woman and a girl. I wish the English language was responsive enough so that we didn't have to define her as one or the other.

There's the girl/guy dichotomy, and then there's the girl/boy dichotomy, and the fact that females have the same word for both makes it tricky, and I'm tempted to call it fossilized sexism inherent in the language.

There is a considerable gray area in terms of maturity and development, so I really like the idea of making your usage context-dependent. For places where you're expected to act like adults, everyone is a man or a woman, but you can bust out the guys/girls for more casual environments.

I would suggest "gal" as a female equivalent to "guy", but I can't bring myself to call a woman a "gal" unless we're both wearing cowboy boots, and I threw away my last pair a long time ago.

I prefer when people (especially my coworkers) call me a girl. However, I work at a very informal job. I am 22 and still, when someone calls me a woman it makes me stop and notice. I may be 22 but I am not sexually active, not a mother, I still live with my parents, and I still work at the same job I did in college. For me, the term is based on experiences.
I also refer to my friends as girls as we are all fairly carefree. But that's just my opinion on the girl/woman debate.

I think you raise a really interesting point here because the distinction between these two labels has bothered me for quite a while. I am 21 years old and often referred to as a girl in professional and academic settings while my male counterparts are given the title of men.

I’m finding it harder and harder to think of when it would be favorable to refer to a female of any age as a “girl” considering the unfortunately negative connotations it carries with it. As someone who is very interested in linguistics, I think this is a very important issue. The real question is does the language dictate the values or do the values dictate the language? For example, when young boys make fun of each other, one of the worst insults is “Stop being such a girl.” I think the root of the problem is the devaluation of the feminine which takes place so often in our culture.

Additionally, I would just like to point out that sex and gender are two entirely separate things. Therefore, it is possible that a “female” of a certain age will not want to be called a girl or a woman, rather a man or something in between for that matter.

You bring up a great point though, and ultimately, my response would be that women should be called women. If "girl" is being used to describe a very young group of people, that's fine. Just don't use it to infantilize someone. I'm all for equality. Where we are referring to men, we should refer to women. When we are referring to boys, we should refer to girls. However, I don't think just calling everyone "people" would be such a bad idea either.

I know that I may be hit for this by some of you, but I call all females age 12 and over a "woman", due to puberty.

At 21 years old, I don't yet feel like a "woman" but hate to be called a "girl" because I am not that either. For me, the term refers to a type of maturity, but not necessarily sexual maturity. I find that there is an in between stage, however, that our language has not developed a term for. I lament the fact that males of this age have easily adopted the term "guy" to deal with this, yet females have nothing. I say we need to bring back "gal" please :-)

I am not sure. I know that I was very angry when a colleague addressed me as "girl". At age 40. As full professor with tenure. And when I complained, somebody said I should feel grateful that I look so young.

I think every female 18+ is a woman. Every prepuberal female is a girl. In between, I'm not sure.

I think calling anyone 'girl' (or 'boy') over the age of, say, 16 is quite demeaning and I for one (as a 26-year-old male) absolute despise when people who do not know me (specifically waiters) use terms of endearment ('sweetie', 'kiddo', etc.) on me. I do not see any problem in calling someone who's 15 a young woman or a young man.

I think adulthood exists more on a continuum, not a black and white thing. There might be "teenagers" working jobs and paying bills while there are also "adults" in their 20s may be still living with their parents with no job.

I believe the difference between child and adult is similar to the difference between straight and gay. It's not "either this or that".. if I am making sense..

It's very simple for me: I always start at the age of majority (in the US, it's 18). If they're over 18 then they are women and men-- under and they're girls and boys. However, if a child acts the the bearing of an adult and shows maturity, I give them the respectful term that I grant to adults by calling them women/men. The reverse applies. If an adult is acting childish, then they lose my respect, and I apply the term meant to address a child.

I personally have always used girl to be equivalent to not only boy, but guy as well (instead of gal), as an informal version of man and woman.

I'm in my mid twenties, and I doubt I'll switch for my contemporaries in informal situations for a long time. In professional situations, I end up using male or female instead of man or woman anyway, so it's never really been an issue.

It was getting married at 22 that convinced me to start referring to myself as a woman. You can't very well call yourself a "married girl." It was kind of startling when I realized that I had blown through my senorita years and that anyone who calls me that is probably just being polite and calls any woman in her twenties "Senorita." I wear a wedding band and think I pretty much project an aura of being married, especially when I'm out with my spouse.

In many cultures, including my own, we call unmarried females "girl", married females "woman". It is directly tied to her "virginity", because one way to to say a female is no longer a virgin is to say she "became a woman". It's also insulting to call an unmarried female a "woman".

It's tied to sexual activity, but I think it kind of goes the same way for males, who are often said to "become men" once they have sex.

I started calling myself and other females "women" in college. However, I still called males "guys" instead of men. I don't know why...

Hmm, I don't know. I'm 21 but psychologically I feel younger. I don't feel like a woman. Not even a young woman. I feel like a girl. But that's just me. I don't think there's anything wrong with it, but it does get problematic for me when socially, 21 is the age that one is considered an Adult. Yet I don't feel that way. I struggle to deal with things on an 'adult' level. I'm having a hard time paying my bills and deciding on a career, and I'm sure my ineptitude with these things is at least partly due to my upbringing in a traditional Bosnian family. Having people do everything for you and walk on eggshells around you because you're a girl definitely doesn't prepare you for Adulthood, I'll tell you that....

I take issue with the word "woman" because to me it brings up all these ideas about what a "real woman" is and suddenly all I can think of is big breasts and swaying hips and babies and seducing men. And that's not me at all. So maybe my goal is to be a Person, which means being a woman (because I guess I am that, technically) but in a way that is not culturally imposed or constructed. I want to be an Adult, but at this point I have no idea what that means, really. To me it feels like some dead end where Adulthood and 'being mature' means giving up your dreams and finally settling into a 'role'. And I can't do that so I struggle because it makes me come off as very immature to others when really I'm just trying to salvage my selfhood. I guess I have some kind of a complex or something.

In closing, the terms woman and girl and how one feels they fit within those terms is entirely subjective, I think. But because society has so many pre-packaged notions about adulthood and, therefore, womanhood and manhood, it can be hard for those of us who don't fit that mold, be it due to upbringing or personal choice, or both in my case.

It gets even weirder when you are trying to define yourself. Right now, at 20, calling myself a woman is still weird. I often still refer to myself as a girl, just because i am used to it. I guess my internal transition from girl to woman is currently still in process...

Oh, I just wanted to add that I very clearly remember being pleased the day a stranger referred to me as a "lady." I was 15, pretty far on the road to sexual development, and dressed somewhat conservatively. I was on a beach and wearing a straw hat and a longish dress.

I generally think of the transition to adulthood happening when a young person becomes independent of their parents, especially financially. Thus, I am 20 and my boyfriend is 22, I don't consider myself a woman or him a man.

I guess this could be a very culture- or class-specific definition, because I could see people who live with their parents their whole life. Or there are those people who live at their parents house until they're 35. Now that I think about it, there are a lot of problems with my definition.

I think it's incredibly demeaning and insulting to claim that anyone under the arbitrary age of majority is definitively not a woman, but beyond that, I'm not sure of much else.

I too have noticed the confusion on this web site. I've seen posts that call females as old as 21 "girls", and as young as 16 "women". I am honestly not sure exactly where to draw the line sometimes.

Personally, I say "girl" if we are talking about someone under 18, and "woman" if we are talking about someone over 18. I fully understand that the age of majority is arbitrary, and not the same everywhere, but determining the appropriate word based on this prevents me unintentionally demeaning a person based on some other attribute.

For example, while it is unfortunate that all things pink and fluffy are automatically associated with women in general, if a particular female honestly likes pink and fluffy things on her on account, I wouldn't want to demean her for that by calling her a "girl" based on that, what ever her age. I would not want to associate particular tastes, or particular interests, or particular behaviours, with immaturity unless they are demonstrably childish, which the wearing of pink, for example, is not.

By using the age of majority (which is the point at which a huge number of other demeaning things cease to be applied to a person, arbitrary or not), I avoid demeaning or promoting anything through its association with a particular maturity level.

This has always been a major issue for me because I neither want to disrespect whomever I'm addressing with an inappropriate descriptor, nor do I want to equate in my own head certain nouns with certain attributes. For instance, my two best male friends I describe as "boys" quite often. This doesn't imply they are immature, but rather implies my familiarity and affection. (Gentlemen, sirs, etc. are also thrown around quite often.) The same could be said for "girls," which I've often used to describe close female friends -- in addition to ladies, women, whatever.

Language is too fluid to be locked into some archaic and/or often-false definitions. The only standard we should truly have is what we're comfortable in saying and hearing.

So in order to duck from the entire argument, in generic and non-familiar instances I've begun using the clinical terms of "male" and "female." With cis and trans in my back pocket, of course.

When a person reaches independence they have reached adulthood. For a female that means woman for a male man. By independence i mean both financially and emotionally.

When a person reaches independence they have reached adulthood. For a female that means woman for a male man. By independence i mean both financially and emotionally.

This is also what I would say, this and also taking full responsibility for your actions and your life. So I would say "man" and "woman" aren't tied to ages, just that we tend to think about them in ages since becoming responsible and independent usually happens at certain age milestones.

I know I try to use women and man with anyone over 18 if only to get them to start thinking of themselves as such.

This is a terrible problem in men's psychology too because "Be a man" and "separating the men from the boys" have become such ubiquitous methods of enforcing the patriarchy.

I'm not sure how this enforces the patriarchy unless you consider being independent and responsible part of patriarchy. In the hypothetical case above about the person working at 16 to pay their parent's medical bills, I'd say "Be a man" or "Be a woman" to them interchangably depend ending on the case. It seems to me that telling girls to "Be a women" would be just as effective as telling boys to "Be a man" as long as it was done in the correct way. It is a part of men's culture which gives them power so why not use it with women for the same reason? Although, I suppose you could say "Be an adult" just the same.

I have a hard time reconciling this as well. I'm going to be starting my MA research and a large component of it will be working with adolescent women. But, I find when I'm talking about this research to people I often use the term "girls" and then feel uncomfortable about it afterward.

I think I see the term as infantilising. I don't like it when I'm called "girl". Calling a woman a girl in some sense, to me, feel as though it removes any sense of agency or ability she has. And I think the same for young women. In some ways it denies women the recognition of being critical thinkers, decision makers, of being powerful persons. Ultimately, I think it denies a woman a social identity linked to being an "adult" (however you define it). In turn privileges the authority of those calling women "girls".

I look really young, and I am small in stature which doesn't help either. I can't tell you how many times I've been called "cute" or "adorable" due just to my height! People have literally patted the top of my head while saying this...
The last time I went to visit my hometown, Iwent to my mother's work to meet her co-workers. One guy patted my head and said, "You're just so adorable, kiddo!" I sort of froze, and couldn't think of anything witty at the moment. I just said, "Excuse me?" He basically just re-phrased what he already said, again, ending it with "kiddo." I told him that I had just completed my PhD work and that if he insisted on referring to me as "kiddo" he'd need to ad Dr. to it.

I am 26 years old and I am a woman. I think I started seeing myself as a woman when I turned 21 years old. I didn't even realize this until an older professor of biology, at my college, a feminist, angrily repriminded a student for referring to older women as "girls."

"I'm a boy, and I'm a man. I'm eighteen" - Alice Cooper.

I think that if someone is old enough to enlist in the armed services, she is probably a woman, though in my old age I find myself applying the word "girl" to people well over eighteen, especially if they are behaving in an immature way.

I want to support the lobby to bring back the word "gal" as the female equivalent to "guy". Yeah, it does feel old fashioned and western, but hey, Wyoming is where we got the vote first. It seems to me that using the word guy for both genders just accepts male as the norm.

Interesting historic point: in Old English before the eleventh century the word "man" meant both males and females. A man was a "werman" and a woman was a "wifman'.

Here's a depressing anecdote on this issue...

My stepdaughter and her friend came home from preschool one day telling me about how the police had visited their class. My stepdaughter said "there was one policeman and one girl who was also a police." Which indicated to me first that the preschool teachers are still using the male-default language (policeman, fireman...) that several of us parents have asked them to change to gender neutral terms like police officer and fire fighter. It also told me that preschool aged kids still think of women who are well into their 30s as girls. So I asked the girls to complete the sentence "there are boys and girls, and there are men and ___________." They stared at me blankly. Then I asked them what they would be when they grew up. After a brief pause my stepdaughter's face lit up, and she said "adults!" So we had a talk about how grown up girls are women just like grown up boys are men. This seemed new to them, and they're both very articulate and well adjusted kids. In fact, my stepdaughter tests at a 7 y/o level for vocabulary and verbal comprehension. So I don't think this is an anomaly, and I think the way kids characterize things really is a reflection of the views of our culture.

Did you just say "GREAT... like terminating a pregnancy." I'm pro-choice, but I hardly believe this alone is a "great" act. It can be a responsible choice, but not every abortion is "great." I'm confused...

All I can do is share my personal experience with this. I hope it's helpful.

I just turned 20, and I struggle to use the word 'woman' to describe myself. For me, the difficulty is trying to recognize myself as an adult, an identity I've never really had before. I have to come to terms with aging, with my new place in the world, and though this is hard for anyone, I feel it is especially hard for me. I was a repeated victim of pedophilia, and for the longest time, my sense of sexuality only revolved around that. Turning 18 was, paradoxically, having all my sexual appeal taken away. I also struggled with emotional and physical abuse at home and had to contend with child services. In many ways, that also influenced my identity. Finally, I have some severe mental health issues. I was hospitalized four times between the ages of 14 and 15, and it terrifies me to think now that if I were hospitalized again, I would not be among my peers nor necessarily my own gender.

Sexuality, family life, and health were all especially constructed for me as being a child... a powerless child. In order to own the term woman, I must come to terms with all of this first. I feel that this is true for many other 'women' as well, and it may shed some light on our reluctance to call ourselves what we are.

Thank you for raising this really great topic BackOfBusEleven!

Thinking about when I start calling someone a "woman" instead of a "girl" I've realized it has a lot to do with my perception of the individual as someone who has started moving away from unquestioning acceptance of what she is told and towards forming her own reasoned thoughts and opinions. Having some understanding of this, I feel like it's a problematic, paternalistic, and presumptive way of categorizing people on my part.

I remember being called out for referring to female college students as a group as "girls" when I was first becoming involved in feminist organizing. I was confused because I had plenty of friends in that group who preferred to be called "girls" and plenty who preferred to be called "women."

I think in that case it makes sense to respect an individual's wishes, but when talking about the larger group to use "women" since it is generally more respectful.

As a trans person who first came out as genderqueer about three years ago "woman" feels weird to me. Hell, I'm still a baby! I never got to be a girl, and I sometimes feel like I'm going through that process now. In many ways I'm clearly much older than three, but in some specific ways related to gender, not so much. Obviously this also depends on context and who is speaking, but "girl" feels great a lot of the time, and I'm 24.

I generally think of the transition to adulthood happening when a young person becomes independent of their parents, especially financially. Thus, I am 20 and my boyfriend is 22, I don't consider myself a woman or him a man.

I guess this could be a very culture- or class-specific definition, because I could see people who live with their parents their whole life. Or there are those people who live at their parents house until they're 35. Now that I think about it, there are a lot of problems with my definition.

I am 21, and don't consider myself a woman or a girl. I consider myself a lady because it doesn't have the age-related connotations of the others. I'm not financially independent from my parents yet (damn expensive education!), but I am independent in a lot of ways, and am responsible and mature. Still, the financial dependence makes me uncomfortable calling myself a woman.

I think the difference for me is independence from parents or caretakers, or an age that I feel is undeniably adult - 30 (whichever comes first). 30 seems like the socially-determined age at which it absolutely is no longer acceptable to be immature and irresponsible. If the person is in an in-between stage, like I am, I call her a lady.

Keep in mind, this is my personal (informal!) distinction. If I were writing some sort of formal, academic, or legal document, I would refer to legal adults as women and men, and those under 18 as girls, boys, chicks, dudes, guys, etc.

I'm 16, and while I'm certainly not a woman yet I find myself bristling a bit when I'm referred to as a girl. Because of my youth I don't react, but I suspect I'll be pretty nasty about it when I'm in my twenties. (The same thing goes for "Miss"--
once I've reached legal majority it will be Ms., or heads will roll.)

I'd never thought about using "gals" as an alternative to guys. I go to an all-girls school, and when addressing us the teachers chiefly use "ladies"-- I tend to follow suit and use "ladies" or "gentlemen" when addressing gendered groups of people.
When referring to myself I use "female". I like the term "young woman," but it really doesn't roll off the tongue-- while "female" may seem to be a bit clinical, I like that it lacks the baggage held by other terms.

For a very long time I flinched whenever anyone addressed a group I was a part of as "girls"-- I associated it with being weak. Now I've relearned how to see it as a qualifier and nothing more, but if that doesn't say how cautious one should be when using "girl" then I don't know what can.

Personally, I know I'll stick to the ladies-gentlemen route. Or "people". I find them easier words to fit into natural conversation.

When conversing with strangers, I like "lady", for myself, and for others (young is a an acceptable prefix when differentiation is required). I am 21, I take a little offence when referred to as a "girl", unless it is by someone younger than me, or I am presenting myself in a very casual way. I have felt this way since I was 17, though I was more accepting of "girl" initially, every time I get it it leaves a more unsavoury taste in my mouth (I rarely get called a "girl" so I take notice when I am). I find it condescending, especially when said by a man. "Woman" is all right, though I would not use it to describe myself at this point in time, as I don't really identify with the image it conjures in my mind's eye. "Lady" may have unwanted connotations for some, but I feel it is the most respectful way to refer to an unfamiliar female.
I feel as though "girl" is like a nickname - acceptable in certain cases, when you are on familiar terms with the woman in question, but very disrespectful to use for a grown female that you are unfamiliar with. I would only use it for a teenager when they are acting young and girlish, and below age 16.

In college, I hear the phrases 'guys and girls' a lot because most college students really haven't made the transition to true adulthood yet. While I'm a bit more independent than some of my friends, I still consider myself a 'girl' in social situations and don't find it demeaning. I refer to my male friends as 'guys' in social situations. The only time 'man' or 'woman' is used to really define someone in their early twenties is in more professional situations. For instance, I am on the Women's rowing team, and my male friends are on the Men's rowing team. When I refer to myself with my career, I am a Woman scientist. However when I got out, I can be 'out with the girls' or 'hanging out with the guys.' I think it's an age/maturity thing, and for social situations, 'girl' isn't really demeaning.

I think there is definitely two dimensions the determine what's appropriate: 1. Maturity level, which can mean the maturity of the person, of what specifically you're talking about, though often it more perceived than actual maturity. 2. Formality, in formal situations you always say man or woman, while in very informal situations you could possibly call a group of seniors boys or girls. However, one is more likely to be mature in a formal situation, and even intentionally immature in an informal situation.

During adolescence, which can mean everything from thirteen to thirty, there is a continuum between child and adult. Yes there is a legal age where you become and adult, but as others mentioned that is very different from being mature. Maturity can mean a lot of things, from being economically independent to handling your emotions well, it is a subjective term. During adolescence girl, gal, young woman, woman can be interchangeable, boy, guy, young man, man are also interchangeable.

Unfortunately girl can mean either a child or a adolescent if used informally. In many parts of the country 'gal' isn't used. It don't think that girl/guy is really sexist, though anyone who calls females 'girls' and males 'men' should be called out.

I'm 20 and in college, working but living at home.

I don't really feel like a woman, because that implies that I'm a grown up. But I've already had numerous life experiences, I'm a legal adult, I have a strong sense of self and determination, so I always refer to myself as a woman.

Plus it makes people uncomfortable and I sort of like that.

I usually err on the side caution and refer to females over 18 as women. Even if they wouldn't self-identify as a woman, I find it less insulting.

@BackofBusEleven

Although I think that your idea of linking the usage of 'woman' to fertility and maturity is interesting and applicable in some cases, I have to challenge that concept as a woman who identifies as queer. There are many different situations in which woman will choose not to exercise her fertility, which may be interpreted as lack of physical or emotional maturity. Perhaps sexual activity and emotional maturity are better indicators of an arrival to 'womanhood.'

I think that there has been some very interesting discussion on what it means to 'become a woman' and when that occurs. For myself, I think that as I became more emotionally mature and shed the sadistic self-obsession of adolescence the word 'woman' began to apply to me. Personally, I think that if we aren't in environments that encourage us to adopt 'woman,' then we must choose to adopt it at our own pace.

as long as i don't get called "ma'am" i don't care.

but seriously, if i'm at work, i'd rather be referred to as a woman. friends and such usually call me a girl and i don't mind that.

You know when I see "girls" used a lot for people who are legal adults? In the context of services for the developmentally disabled, or residential care for people with psychiatric/psychological issues. I don't mind it when it's used socially as an equivalent of "guys", but when it's applied to people over 18 who are being infantilized because of the services they require? CREEPY.

At age 18, in American culture, people are legally and socially regarded as adults. An underlying belief here is that people 17 and younger, in general, lack the full capacity that an adult has for making decisions intelligently.

Our language should reflect that, so in America I would say it's appropriate to apply the word "woman" to females of age 18+ and "girl" otherwise.

Common sense needs to take priority here -- a 17 year old can be just as capable as a 19 year old, but if we're just talking about terminology, why would we tell a 17 year old "we're going to call you a 'woman' even though in the general context of society and law you are not regarded as an adult"?

unlike many people here, i dont think that you can base it on financial independence. ive read that in the united states, the average young person (male and female) is not fully financially independent from their parents until age twenty-five. is a twenty-five year old female ever a girl really? i am a 22 years old who had been financially independent (ie paying my own rent/bills/student loans) until three months ago when i ended a relationship (and lost half of the rent) and was laid off from my job. since then i have had to move back in with my mother. was a woman 6 months ago? am i a girl now? have i lost my rights to womanhood because i have fallen on hard financial times and needed the help and support of my family? to base womanhood on financial independence is a very class-limited viewpoint because it does not take into account the varying financial situations of girls and women.

i think that the difference is more contextual than empirical. i do not mind if a friend/acquaintance/peer uses girl when describing me (as in, "she is the girl in the glasses at the end of the bar" or even "hey girl, hows it been?") because its use is a non judgmental description of gender-identity. but in more formal situations where you are expected to show respect and be respected (ie work or college), i would feel as though the use of girl would be pejorative and imply as though i were not a peer of the speaker. it would be the same if a male co-worker of mine were to be called a boy. the implication is the same.

just an anecdote: i went to smith college for a couple years (but had to withdraw because of "financial concerns" aka not being rich) and there was a popular tshirt in our bookstore that said "we're not a girl's school without men, we're a women's college without boys"

Personally I use the terms guys/girls for peers or for teens and save men/women for those that are significantly older than me or that are not directly part of my peer group. Perhaps this is because I still feel young but it always feels strange to call friends of mine men/women.
As for the differentiation between girls and women, from your examples it seems that the posters on Feministing use the term "girl" when they want to evoke the vulnerability of the victim and is perhaps an unconscious means of unearthing more sympathy. Whereas the term "woman" is used when the poster intends to display the strength and power of the female in question (I am woman hear me roar). I don't think these terms are attributed consciously but it works. As for the overall designation of the titles girl and woman ( as well as man and boy) I personally believe there is no hard and fast rule as it depends on a case by case basis as you stated in your examples. There are indeed some people who act and seem like women/men when they are only 15 while others certainly still act like girls/boys into their late 20's and beyond. It's an interesting topic to speak about but my metric determing title is often maturity and as we all know maturity is a highly subjective and varied concept from person to person. But I'm still likely to call my contemporary females girls simply because there is no equivalent to 'guy' and woman just feels too formal to me.

Young Lady always sounds so patronising, I don't think in my life I've ever heard it said in a sincere way, and it really gets my goat now that I'm over 20, honestly, I even prefer girl to young lady, But I generally call people by a non gender group name, and to me guys qualifies as that, or at schools class, or ladies and gentlemen

among friends though, we are still defintely boys and girls.

Please delete this trolls message. I also got an idea; why dont we do this to MRA websites?