To splatter is for a liquid to hit a surface and break into many small drops that spread out and stay there — hot oil splatters out of the pan, mud splatters up the side of a car, paint splatters on the floor. You can also splatter something yourself: he splattered paint across the canvas; the bus splattered us with dirty water. It is stronger and messier than 'splash': a splash is one body of water moving, a splatter is many scattered marks, and it usually leaves something behind that you have to clean. As a noun, a splatter is that pattern of marks — a splatter of ketchup on his shirt. The word carries into film talk, where a 'splatter movie' is a horror film with a lot of blood, and into art, where splatter painting means throwing paint at the canvas. There is a related word 'spatter', with one L, which means much the same and is a little more formal or literary. Because of the horror-film use and the blood picture, splatter can sound violent in some contexts.