look up any word, like eiffel tower:
 
1.
With a stranger:
Fighting words. Used as an insult.

Between friends:
A person who has committed a small act of bitchery. The connotation is similar to that of a bro, brosky, homie, or boy- but this is the girls version.
example one (not friendly)
Girls in a club
Stranger 1: *spills drink on stranger no. 2*
Stranger 2: You wanna go, Bitch-slice?

example two (small act of bitchery between friends)
Friend A: That was your ice cream? Sorry... I kinda ate the last spoon...
Friend B: Ugh, you bitch-slice.

example three (between friends)

Friend 1: WASSSSSSAPPPPP bitch slice?!
Friend 2: AHHHHH QUE PASO!??
by latenightsgreatnights August 03, 2009
 
2.
used to describe someone being a complete bitch
Joe: I will eat you
Bill: Your such a Bitchslice
Joe: sanfasizzle
by BroJoe555 March 21, 2010
 
3.
When Eating a Pizza and it is incorrectly sliced so that one slice is Extremely large in compare to the others
*Opens Pizza box and takes slice*

Derek: you asshole you took the Bitch Slice!

David: Gargle my balls cunt!
by DerekTheDestroyer......Kinda:/ April 16, 2010