Answer:
It's a Scots dialect term, a plural of "you".

In the US it is also used colloquially (as a plural form of you), often for humorous effect. It is seen in stereotypically ungrammatical parodies of "mobster" language, e.g. "Youse guys is gonna get it".
First answer by Angelito149. Last edit by Dfoofnik. Contributor trust: 2559 [recommend contributor recommended]. Question popularity: 14 [recommend question].