Being depressed over something stupid/silly or for a seemingly stupid/silly reason.
derpressed kid: "im depressed because my mom wont buy me black ops."
depressed kid: "what? i think your derpressed dude because thats no reason to be depressed. i'm depressed because my mom ran over my dog!"
a person who acts strange,weird, and/or random, usually quite fun to be around due to the fact that this person is an oddball and does and/or says interesting things.
derp: -randomly shouts in the middle of the sidewalk- "Who put this beaver in my pillowcase!!!!"
-friends laugh and giggle-
The act of returning to a game you haven't played in an extended period of time and having completely forgotten how to play, how your abilities work, what you're supposed to be doing. or all of the above.
Person 1: Man, it has been so long since I last played World of Warcraft that I have no idea what I'm doing.
Person 2: sounds like you've got a case of gamenesia.