A nooby or pointless person, this word can also be meant as a way to say someone is stupid. See noob for the way derp can be meant in video games.
That guy is so derpy. He is totaly a derp, does not even know how to reload
Basically, a phrase used when A mistake is made
Ashlyn: Amy you dropped the donuts
Amy:DERP
An offensive way to say someone is bad at any video game, or looks derpy, like slowpoke.
One of the most amazing words ever
I love the word derp.... DERP!!