'Bint' is one of many words used instead of 'girl' or 'woman'. It usually implies sexual availability. It is a bit dated, it was much used by British troops during the World Wars.
Personally I'd use the term if the girl wasn't the best lookin' in the world. i.e. "I pulled some old bint last night."
The word bint probably originates from Arabic, where it means "daughter of" (and often appears in female names in Muslim countries, as bint or binti, cognate with bin "son of"). It was picked up by British soldiers derving in the Middle East, and as suggested above, is mildly derogatory, and now dated.
Warbling is a reference to singing but can also be used when somebody is talking on and on and wont shut up. so if somebody is warbling it tends to be a derogatory term