The recent observance over time of the changing definition/usage of the term "bitch". Specifically, Bitch Theory describes the change from the word bitch being derogatory, to it being a term for coolness, much like the change in the definition/usage of "nigga" in recent times.
1. Females use the term bitch to demonstrate coolness amongst themselves.
2. If a male calls a female a bitch it is seen as unacceptable or derogatory by females and males.
3. A less direct term females use in place of bitch is "bitty(s)" or "bittie(s)".
The Bitch Theory is basically a new double-standard.
Bitch Theory in action:
Example 1: Female: "I'm a hot bitch! :)"
Example 2: Female to Females: "C'mon bitches, let's go clubbbin' ! "