Although quite simmilar to being an assfish, it is used more as a personal denunciation rather than that of a group
(syn) idiot, assmunch, ass capitain, ass pirate, assclown, stupid-ass bastard, fuck face,asshole
(ant) genius, trustee, smart, intelligent, knowledgable
Example: (after someone punches you) "what the hell you friggin' asstuna!!!