1. the sexual act of following anal sex immediately with oral sex, which causes residual fecal matter to coagulate on the recipient's upper lip, resembling a Mexican handlebar moustache
2. Unexplained sexual position taught by South Park character Mr. Garrison to his kindergarten class.
(1) 'Naw, I gave that slut Jessica a Filthy Sanchez, dude, not the other way around!'
(2) 'Ike, do you know what a "Filthy Sanchez" is?'
A group of people that rolls 600 pounds deep, which is really no different than if one person acted like the 600 pound gorilla all by themself, it's just bullying spread around a group to fuck with somebody. Just like each person has an asshole, and to some degree is an asshole, a collective 600 pound gorilla has a collective asshole so that no one person has to take responsibility for being the asshole or the one who said this or that.
A sports team/organization that by all conventional metrics should not have success/wins in whatever activity, but somehow by apparent luck they find a way to win.
example: "The 2013-2014 University of Auburn football team was the team of destiny that year that managed to make it all the way to the championship."