The drug emitted from the brain when one is derping on addictive social media sites. The more you derp, the more derpamine is emitted to keep you derping.
While I'm trying to have a conversation with him, Jeremy keeps checking his @'s for another hit of derpamine. What a cunt.
Pajama casual is a term used when working from home and preparing for a video conference. All business above the waist and your pajama pants down below.