1. To slosh or spatter onto someone or something. Ice-cold water kept splashing all over us as we navigated the treacherous rapids in our kayak. Make sure you put a lid on that pan while you're cooking bacon, or grease will end up splashing all over your brand-new shirt.

2. To completely cover or drench someone or something with some liquid after sloshing or spattering it onto them. In this usage, a noun or pronoun is used between "splash" and "all over." I tripped as I was approaching the table and accidentally splashed wine all over the guests. The whale leaped up and came crashing back down into his pool, splashing water over the entire audience.