to grab-a-bite basicly means to get some food or to eat something.
Jeff: Oh goddamnit, I'm starving. I gotta go to Charcoal's Grill and grababite!
by Santacruzshores January 11, 2006
A slang term meaning to eat something
Hey fellas, let's stop by that burger joint and grab a bite.
by Sajajd jafari December 12, 2013