A level up from a cup-a-cheese, a Hapoopen is when you fart in your hand and throw it at someone's face. The more you sound like Ryu from Street Fighter, the better
Guy 1: *fart* *chuck* HAPOOPEN!!!
Guy 2: *sniff, sniff* aw dude what the fuck!?
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.