Used as an expression to accompany giving someone
the finger, telling him or her to literally consume it; therefore, you are
in essence symbolically telling the person to suck dick.
This was used to great effect in John Waters' film "
Pink Flamingos."
"
Eat the bird, bitch!" (from the
aforementioned film)
Jim: If this party isn't fun, I'm gonna be pissed.
Tim: Shut up, Jim.
Kim: Yeah, Jim. Eat the bird.