Meaning of “bum” - Learner’s Dictionary

bum

verb [ T ] us uk /bʌm/ present participle bumming, past tense and past participle bummed very informal

to ask someone for something, such as money or cigarettes, without intending to pay for them:

Hey, could I bum a cigarette?

(Definition of “bum verb” from the Cambridge Learner’s Dictionary © Cambridge University Press)