An expression used when a person, or yourself, has done somthing extremely stupid and dopey
Person 1: Dude, I just hit my head on the door.
Person 2: HERP DERP.
by Kommandant November 25, 2009
A phrase said by idiotic morons who think they are cooler then they actually are.
by mmmmmhm October 17, 2010
She was tryin to slob on my knob, and I was like 'Nah, trick I aint tryin to get no herp derp, get off my dick!'
by ghobi and tcap October 5, 2010
to act in the way of sexual conduct, and to release tension in the process.
He herped her til she derped.

Go herp yourself.

He derped on her face.

They herp derped
by nfalse February 14, 2011