bitch
n. one's girlfriend. (Crude and mostly jocular.)She's my bitch, and I love her.Me and my bitch really like this kind of stuff.
old lady and old woman
n. (one's) girlfriend.My old lady and I are getting married next week.I got my old lady a bracelet for her birthday.
pussycat
n. a woman or young woman; one's girlfriend. (Also a term of address.)Hi, pussycat. Don't I know you from somewhere?Who was that yummy pussycat I saw you with last Friday?
sister
n. a (female) friend. (Originally underworld. Sometimes a term of address.)Hi, sister! How ya doing?Come here, sister. I gotta have a word with you.
(soul) sister
n. a black person's female, black friend.One of the soul sisters dropped by to talk.A sister called, but didn't leave her name.
wife
n. a girlfriend. (Collegiate.)Me and my wife are going to Fred's this Friday.Ask your wife if she wants to come along.