Popbeef 

The act of two popular music stars, usually female, disagreeing on some sort of issue, relationship, or simply believing one is a better artist then the other. ie. the nikki minaj v. lil kim fiasco of 2011.

Origins unknown, but brought to light by someone going by the screen name "mac a belly", who in turn, is a huge faggot.

"Yo dawg, you hear about the popbeef between Brittney and Katy Perry"

Popbeef by Silverbeam January 3, 2012