Derpderp 

Nickname of the Sea Otter Water-type starter for Pokemon Black/White on the GameFAQs Pokemon Black/White boards, so named due to its goofy, uncompelling design, especially compared to his Grass and Fire counterparts. Described as "the bastard child of a Jynx and a Bidoof" by many GameFAQs forumers.

Derpderp is only sad because he wishes he were a Smugleaf

Derpderp by agnryman May 28, 2010

Berp a derp derp 

A phrase used to express emotion, typically confusion or happiness.

Suzie: "I just love ice skating!"
Johnny: "Berp a derp derp! What?"

Berp a derp derp by YoGrannmotha August 28, 2010

derp-derp 

A small dog possessing one or more of the following characteristics: bulgy eyes, squashed face, eyes that look in two or more directions at the same time, wandering lung, or comically vacuous expression. In short, any dog that arouses feelings of pity, revulsion, and the sneaking suspicion that it would have been kinder to have strangled it at birth.

E.g. pugs, Boston terriers, French bulldogs.
For the origin, do a google search for "hurr durr derp derp derp"

Is that a derp-derp or is she just squeezing her dog too hard?

derp-derp by Boston Terrierist May 10, 2009

derpderpderpderp

the sound that the mythical derpasaurus will make when excited

"Hey derpasaurus! Do you want to go for a walk?"
"DERPDERPDERPDERPDERP!

derpderpderpderp by Derpasaurus_Rex55 November 28, 2018

derpherp 

Bigger derp then the normal derp as they simply add a word that rymes with derp at the end

Derpherp derpshlurp derp herpcurpflurpburp

derpherp by Burpschlurp December 13, 2017

Derpaderp 

A case in which a person or animal is so cringy that there are oddly funny

I felt like such a derpaderp when I horribly answered the question wrong.

Derpaderp by Da flash (comic) March 4, 2018

Derpaderp 

DErp

Derpaderp

Derpaderp by wufiwiwkwfsj May 8, 2018