butter不是可数，butter作为名词时意思为黄油或黄油状之物；做为动词时意思为涂上黄油.是不可数名词。

例句

１、Pour the melted butter into a large mixing bowl.

把熔化的黄油倒在一个搅拌用的大碗里。

２、She spread pieces of bread on the counter and began buttering them.

她把几片面包摆在台上，开始抹黄油。

３、These chaps know what side their bread's buttered on.

这些家伙知道怎样做对他们有利。

用法

butter sb↔up

(informal) 以甜言蜜语巴结某人；奉承；拍马屁 

to say nice things to sb so that they will help you or give you sth