bad, wrong, or worthless bum advicechiefly NAmer inferior or worthless bum adviceinjured or damaged a bum knee
an idler or loafera homeless person who lives on the streetsan incompetent personsomebody who devotes his or her time to a specified recreational activity a ski bum a beach bum [prob short for bummer2]
verb intranschiefly NAmer, informal (+ around) to spend time idly and often travelling casually She bummed around for three years before she got a job verb transinformal to obtain (something) by begging; to cadge [prob back-formation from bummer2]