The crustybrown material that gets transferred to the rear of the toilet seat or underwear, resulting from the accumulation of fecal matter at the top of an unclean, too-far-rear-wiping person's ass crack.
I almost sat in the hefty butt smudge that you left on the seat!
Noun. A visible smear of faecal matter deposited on the surface of bathroom sanitary ware. The deposition process being the muscle- and gravity-assisted expulsion of moderately soft excrement from the anus.
1) Tarquin, was it you who left yet another revolting poop smudge in our shiny new toilet?
2) Valdemort, that poop smudge you left is the work of the devil!
3) Felicity, I had no idea that posh girls could leave a poop smudge like that!
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.