Longman Dictionary of Contemporary English - butt

~1 n 1 be the butt of to be the person or thing that other people often make jokes about  (Paul quickly became the butt of everyone's jokes.) 2 »CIGARETTE« the end of a cigarette after most of it has been smoked 3 »GUN« the thick end of the handle of a gun  (a rifle butt) 4 »CONTAINER« a large round container for collecting or storing liquids  (a rainwater butt) 5 »ACT OF STRIKING STH« the act of striking someone with your head 6 »PART OF YOUR BODY« AmE informal the part of your body that you sit on; buttock  (- see also a pain in the ass/butt pain1 (3)) 7 get your butt in/out/over AmE spoken used to rudely tell someone to go somewhere or do something  (Get your butt out of that bathroom now.) ~2 v 1 to hit or push against something or someone with your head 2 if an animal butts someone, it hits them with its horns butt in ~ phr v 1 to interrupt a conversation rudely  (Stop butting in!) 2 AmE to become involved in a private situation that does not concern you  (Things were going real well until you had to butt in!) butt out ~ phr v AmE spoken used to tell someone to stop being involved in something  (This has got nothing to do with you, so just butt out!)