Definition of "Bum" :
noun: the fleshy part of the human body that you sit on
noun: person who does no work
"A lazy bum."
noun: a person who is deemed to be despicable or contemptible
"Throw the bum out."
noun: a vagrant
"He tried to help the really down-and-out bums."
verb: ask for and get free; be a parasite
verb: be lazy or idle
"Her son is just bumming around all day."
adjective: of very poor quality; flimsy