Sub being short for subwoofers in the trunk. When someone pulls up beside your vehicle with their music blaring and you don't want to look weak so you turn yours up too.
Hey man, you hear that car? Sounds like a subchallenge to me.
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.
We have a Zoom meeting in a few minutes and I’ll probably go pajama casual.