This rather graphic expression is hard to utter with a straight face. It may be a synonym, quite generally, for sexual activities likely to generate odiferous, wantonly distributed bodily fluids.
It may also refer, more particularly, to finger banging.
"Hey man, smell my finger! I was slinging stank the whole movie!"
the act of being a stank and then people put those stands in the squad stank. the squad stank mainly consists faggots, assholes, ugly bitches, and bitches