Has mulitple meanings. It can be used as a slang word for "bitch" or as a greeting.
What up biiit(bitch)? gotcha biiit (bitch)! BIIIT!
Word originating somewhere in the midlands UK (probably in Stone) meaning "good bye". The 'iii' part of the word is uaually greatly emphasized.
"catch ya later bitch. inna biiit"