The distinct sound made when a man's testicles and a woman's ass (nalgas) violently collide during sex, typically when hitting it from the back.
I don't know about you guys, but last night I was involved in some serious nalga-clapping!
When a man is extremely sloshed (drunk) and has sloppy, wild, sweaty, loud, smelly, and great sex with a woman. Be advised slosh fucks have been known to occur with fat women, so the morning which follows the slosh fuck may be extremely regretful and or awkward.
Dude, last night I pounded far too many beers at the bar. Then there was a fat woman, who had NFL linebacker potential. For some reason, after a twelve-pack, she looked good. Anyway, I slosh fucked this fat lady for two hours and it was fucking great!