Bird

British slang word for woman.
Originates from London where prostitutes where refered to as birds with each area of London naming their whores after different birds.
In modern times this meaning has been lost and bird is used by working class people to describe a woman in general, not in a derogatory manner.
Chicks being young women (usually a pretty one and old bird meaning... well you can work thst one out yourself.

What did you so last night, fella?
I went to the pub with my bird.

I shagged an old bird last night, it was the best bonk I've ever had.