spatter up (something)
To coat something in drops, globs, or small amounts of some liquid. Be careful with your painting—you're spattering up the floor! Make sure you change into some old jeans before you go on your walk. I don't want you to spatter up your nice clothes with mud!
spatter someone or something up
to get drops of a liquid or bits of something moist onto someone or something. The painter spattered his partner up when he dropped the paint bucket accidentally. The falling paint bucket spattered up the wall.