skidmark 

A poo poo stain in your undies that is usually centralized, but not restricted to, the area that makes contact with the anus. Usually a sign that means you need to use toilet paper. WARNING: should you encounter skidmarked undies, dispose of them in short.

Laura Shell left a skidmark in her undies and decided to keep them as a souvenier

skidmark by nonselfpooper July 31, 2007

Lipstick skidmarks 

When lipstick gets smudged on a cock while giving a blowjob

She left several lipstick skidmarks on my cock last night. I loved it!

Lipstick skidmarks by ButlerX July 14, 2017

reverse skidmark

Shit stain in your underwear from ass fucking someone

Dear, why do you have a reverse skidmark in your jockeys?

reverse skidmark by Captain Khaos October 15, 2017

skidmarkalgia 

A disorder characterized by brown streaks in the patient's underwear, usually in the rear. This condition is often misdiagnosed as skidmarks. The difference between them is that skidmarkalgia is typically wider spread and thinner, whereas skidmarks are more centrally located and darker. The exact causes are unknown, however anecdotal evidence suggests that fisting may be the primary cause skidmarkalgia.

“Maybe skidmarkalgia can be induced by fisting, FF, but not fibromyalgia.”-Village Voice

skidmarkalgia by madcow3417 June 22, 2008

pakistani skidmark

The act of stuffing a partners lips up ur ass and releasing a mighty strand of shit out.

It looked like Krusty had a Hersheys moustache when I gave him a Pakistani skidmark

pakistani skidmark by cary wichaven August 13, 2007

Skidmark Cobra 

A Skidmark Cobra is the result of taking a dump, usually in Africa or someplace, and discovering you are not alone when a cobra raises its head between your legs. At this moment, you realize your only chance is to grab the cobra's head quickly. Once securely grabbed, you reach back and fish out the cobra's tail and proceed to floss your butt until sufficiently clean for day-to-day use, thus dominating said cobra.

I didn't know there was a snake in the toilet. So, when he poked his head up I Skidmark Cobra'd with him!

I'm a Skidmark Cobra of AGO.

Skidmark Cobra by He-is-man December 17, 2008

skidmarks 

Brown racing stripes in tighty whitey underwear

Will Tide get out skidmarks?

skidmarks by Mike Easter March 15, 2003