Queer is one of my favouritest words in the English language - favouritest being another word I like, although that's not strictly speaking English. As I was growing up, I heard queer used to mean several different things:
(1a) adjective: odd, amusing, eccentric; "John looked terribly queer in his new wig and nobody could take him seriously."
There is also the Lancashire/ Yorkshire expression "There's none as queer as folk." (meaning there aren't anybody who is as strange as what people is, so to speak).
(1b) adjective: odd, sinister. "Shortly after his wife disappeared, Mr Smith was seen digging his garden in the middle of the night. There was something queer about the whole thing."
(2) adjective: unwell. "Jenny was sent home from school with a poorly tummy; the poor kid did look ever so queer."
(3) adjective: impoverished. "Sally said she was queer this week so I leant her a fiver."
sometimes used as down Queer Street. "Since the factory closed, the whole family has been living down Queer Street."
(4) verb: to spoil or pervert something. "I'm afraid my experiment with coriander has queered the entire soup." There is also the expression to queer someone's pitch, to sabotage one's plans, as in "Harriet didn't really want the job, but when she found out I wanted it more than anything, she decided to apply just to queer my pitch."
(5) adjective: homosexual or else not heterosexual. "He doesn't like football, so he must be queer."
These uses undoubtedly vary from region to region; I know my Yorkshire and Suffolk grandparents use the word quite differently. Incidentally, at least the first three of these queers are used in the Hitchcock classic The Lady has Vanished, my favourite being when the lady in question is described as "A queer old bird" (in the sense of 1a). I myself aspire to such a description should I live long enough.
In most of its descriptive uses it is rather vague and non-committal, not even as strong as peculiar. This subtlety and its ambiguity has always made it a rather funny word. On The Fast Show, Paul Whitehouse's Arthur Atkinson, a parody of Arthur Askey, had two inexplicably funny phrases (pretty much all he said); "Where's my washboard?" and "How queer!"
And perhaps because of all this, queer represents probably the most successful reclamation of a term of abuse by a disadvantaged group. Of course, it probably never had quite the spike of the N word, cripple and others, it is a soft word and has become the most inclusive way to describe that group of people who are not straight. After all, without the cultural baggage, bisexual (for example) is no more pertinent than prefers blondes or monogamous.*
[And while I am on words bisexual is a rubbish term. What's this "bi" malarkey? The defining experience of being this way is that one's sexual wiring fails to categorise the population into two opposites with nothing in between. Some people have tried to overcome this with the awful pansexual (which sounds like you fancy everyone) and the even worse omnisexual (which sounds like you fancy everything). Never mind.]
There is, of course, the dyslexic's nightmare which is... I'm sorry, but even now I'm thinking BLT, even though I know it should have a G in it somewhere. But what is the significant thing that makes us a group? Not that we deviate in this way or that, but what we deviate from and the political and social implications of that.
I'm not altogether comfortable with using this label to describe myself because I have the good fortune of having a heterosexual life-partnership, but then perhaps it is those with the most privilege who have the most responsibility to show solidarity (I'm not sure - my concern is that I might not be entitled to the word, not that I would be ashamed of it).
However, I think I could probably be described as queer in a few others senses and I make it my habit to use the word in every sense and at every opportunity. Which may seem a little queer, but that's the way I am.
* Sly Civilian has written some great stuff on this subject.
On a completely unrelated subject, Maddy puts everything into perspective with the excellent telling of her very scary Christmas in Russian Roullette. This was such a great post it needed to be mentioned here.