To me, it meant "Hot Chick" when I put the Spanish equivalents of Hot and chick together. Say it to a Mexican girl, however, and the combination will probably get you slapped silly. To Mexicans, it's just another way of saying "Whore." According to a friend from Venezuela, however, "chica caliente" would mean pretty much what I intended, "realy good-looking girl."
When I said she was a chica caliente
She slapped me like I'd said she was a whore
My Spanish leaves a lot to be desired
Guess I'd better learn a little more