It is when you have diarrhea and you eject your watery feces all over your partner during intercourse. The diarrhea has a muddy appearance and is slippery (like a slip ‘n’ slide) which is why the term “mudslide” is used.
by David Cantonicle September 19, 2006

Having vaginal intercourse with a girl on her period. Followed by anal sex with a penis still covered in period juices.
"My friend got weirded out having sex with a girl on her period, so he flipped her over and gave her a crimson mudslide"
by Hugh Gass August 31, 2005

by Postal Dude August 7, 2006

Drink made with Patron Cafe and Monster Mocha. Adding a shot of patron silver makes it a Dirty Sanchez.
by Kirby68 September 11, 2016

by Big dong6969 October 26, 2022

When you have to release your fecal matter but have a sports practice, so you let it out in your compression shorts. Thus, creating a mudslide like environment in your pants with your own feces.
I had soccer practice after school and had no time to use the bathroom, so i ended up with a mongolian mudslide.
by Chet chu betcha September 13, 2017

A Siberian mudslide can be performed via multiple sexual positions and among both heterosexual and homosexual partners, however doggystyle is the preferable position for maximum value. It is also recommended that you ingest a large helping of horse laxatives approximately 30-40 minutes before sex. After ejaculating onto your partner's back (preferably as high as possible without entering the neck area), quickly point your anus onto the semen that you've just laid and defecate as much as possible before your partner moves. Your partner will quickly realize what is transpiring, causing him or her to quickly jump up, thus causing the whitish-brown semen feces explosion to slide down his or her back, thus resembling an icy mudslide in Siberia.
Mike 1: Yo you'll never guess what I did to my wife last night!
Mike 2: Dude what???
Mike 1: I took 30 grams of pure bear laxatives, came on her back and gave her a good old Siberian mudslide.
Mike 2: Dude no way, let me get some of those laxatives and I'll try it tonight!
Mike 2: Dude what???
Mike 1: I took 30 grams of pure bear laxatives, came on her back and gave her a good old Siberian mudslide.
Mike 2: Dude no way, let me get some of those laxatives and I'll try it tonight!
by Mike and Mike the Accountants February 10, 2017
