Reply #2: are you talking about urbandictionary?

[ant]

I'm just wondering waht the "user created dictionary" is.

In any case, OED does have a definition for it:

As a verb: trans. To deliver a stinging slap to (a person), esp. in order to humiliate one regarded as inferior.

As a noun: A stinging slap or blow, esp. one delivered to humiliate a person regarded as inferior.

I believe the bitch=woman=inferior part is the problem here.

However, I also found this (http://www.askoxford.com/pressroom/archive/?view=uk - click on "new words in the Oxford English Dictionary"):

bitch-slap
• verb US informal deliver a stinging blow to (someone), typically in order to humiliate them: I would have bitch-slapped him for talking that way.
- ORIGIN 1990s: originally black English, referring to a woman hitting or haranguing her male partner.


So, it seems that the origin does come from women hitting men, but the definition used now is about hitting inferiors, which goes with the pimp sort of interpretation, which is what I've always understood it as.