2. (metaphorical) unforeseen, unintentional, negative consequences of a person's actions.
2. Neil realised he had incurred splashback when he recognised his girlfriend's mother as the older woman he had picked up while drunk the previous weekend.
Its bad when it happens in your own toilet - Its worse when it happens in a public one.
Generally occurs only after you've already pissed in it.
Chubbs:Alright, have fun, and watch out for the splashback!
2. When you stand too close to a urinal whilst urinating and urine splashes back onto your shoes and/or legs.
"Hey Joe, what's that all over your shoes?"
"Fuck don't you just hate splashback?"