show displeasure, as after a performance or speech; hiss
English Slang Dictionary
1. a term of endearment, like baby 2. an expression used when someone stares at you for a long time and doesn't speak to you; you say boo!! "I said boo to that guy who just stared at me in the library" 3. a name given to a recluse, or someone strange and antisocial, as in Boo Radley from To Kill A Mockingbird:"Watch out for Boo; he might be a serial killer" 4. your boy/girlfriend: "He's my boo"
File Extension Dictionary
Microsoft Booasm.arc Compressed Archive File Boo Class File Kermit Protocol Binary Bootstrap File Image File IBM BookManager Book