Sticking your entire head into a vagina.
"Somewhere, to what remote and fearsome region I know not, my head has gone. I was with her the last night she lived among men, and heard her screams when the thing came to her; but all the peasants and police in County Meath could never find her, or the others, though they searched long and far. And now I shudder when I hear unimaginable and blasphemous sounds, the sounds of...a taco hat."
by Joy Brown January 14, 2009
Similar to tea-bagging, taco hatting is the act of domination another by placing one's vagina onto the head and/or face of another to establish ownership
I was playing video games last night and after I got fragged some girl came up and taco hatted my corpse
by Nargle September 13, 2009