noun

a vagrant.

bums had been known to wander up to their door and ask for a sandwich

tramp,vagrant,vagabond,homeless person,derelict,down-and-out,itinerant,traveller,drifter,wanderer,person of no fixed address,beachcomber,ne’er do well,good for nothing,outcast,pariah,beggar,mendicant,hobo,bagman,sundowner,swagman,streety,crusty,bag lady,dosser,derro

verb

get by asking or begging.

they tried to bum money off us

scrounge,beg,borrow,sponge,touch someone for,scab,cadge,sorn on someone for,mooch,bludge