Used to call your friends this. Way different meaning than a babe or baby. Girls usually call each other this. If a girl call a guy this it doesn't mean anything, she's just being friendly.
BOO is when you jump out and try to scare them by saying boo! BOO does NOT mean a boyfriend or girlfirend as the chavs above decided to put! grrr get it right fuckers!!!
person: BOO!!!!
person 2: whos dude you scared the crapoutta me!
intra. v.
(bu)
1. Name of cute little girl in Monsters Inc. who came into the monster world and terrorized Mike Wizowski and James SUllivan, the leading scarers at Monster Inc.
2. Very cute girl who wore oversized, pink shirt and had pony tails.
3. Yelled "Mike Wizowski!" all the time in a cute high pitched voice similar to butter on a bald monkey.