Used in graffiti, as with the other definitions, it is to steal someones idea/style. Used by true hip-hop loving graffiti heads, the guys that have skill and have the right to critique others work. Not the gangs of filth that spread their messy skribble tags and would die if they ever attempted to design a piece.
'Damn skarab totally bit Rats style' Or 'That piece is a bite off Rats style if I ever saw one'
In an extreme case one may bite your tag name, esp. if you have built a name for yourself.