What is Butter ?
Butter is (noun) a yellow fat made from cream, used on bread or for cooking Could you pass the butter, please? Don’t spread the butter so thick. Fry the mushrooms in butter. (NOTE: no plural: some butter; a knob of butter) (verb) 1. to spread butter on something She was busy buttering slices of bread for the sandwiches. 2. to butter someone up to flatter someone, to praise someone without really believing it to be true (informal.) Just butter up the boss a bit tell him how good his golf is.
source: Easier English, Student Dictionary Upper Intermediate Level