"My bird" is BE. In AE it is "my chick". They are not grossly offensive but should be used with caution as they may offend some females.
To my knowledge it's not properly used with females. There's a similar misunderstanding (especially among women) about the word
pussy as applied to a person. It's a term meaning a wimpy or squeamish
male. Women are simply not called by that term.
"I made him my bitch" is a similar situation. It was originally limited to prison slang (as Mr know-it-all said), and so of course was picked up on the street by all sorts of wannabes, pussies who never did a harder day of time than an overnight visit in the drunk tank.
From there the straight world picked it up and got it
all confused, the way women do when they hear a guy call someone a pussy.
What sense does it make to call a woman a pussy? And how can you make a woman your bitch? The closer you get to the
original users of both terms, the more obvious this illogic gets.
Office people calling a gofer or other such lacky their bitch? Please! That's stretching analogy to the breaking point, by people who don't even "own" the word-- that kind of sycophantic imitation by pasty-whitebread bozos who "never get out much" has happened with the vocabularies of sub-culture in-groups since the days of the early-50s hipsters, and is much scorned by members of the crowd who originated the terms.
"Office worker" types in polyester 3-piece "leisure suits" and blow-dried "hippie" hairdos with sideburns down to their collarbones used to nod and say "oh, I'm hip to that." Yeah sure you were.
I do agree about the biker exception, though. Never get a hard-on while you're riding bitch, by the way, it might get you a funny reputation.
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