look up any word, like dirty sanchez:
 
1.
the act of eating a gentleman's dick
I am sooooo full from eating his D.
by lick my c August 24, 2003
 
2.
What one says to a person they are mad at or joking around with. D is just a nice way of saying dick
Paul: Yo Aaron, wanna go nut butting?

Aaron: Maaaannn, go Eat a D!
by Aaron East August 20, 2012