a person who avoids work and sponges on others; loafer; idler.
a tramp, hobo, or derelict.
Informal. an enthusiast of a specific sport or recreational activity, especially one who gives it priority over work, family life, etc.: a ski bum; a tennis bum.
Informal. an incompetent person.
a drunken orgy; debauch.
verb (used with object),bummed,bum·ming.
Informal. to borrow without expectation of returning; get for nothing; cadge: He's always bumming cigarettes from me.
Slang. to ruin or spoil: The weather bummed our whole weekend.
verb (used without object),bummed,bum·ming.
to sponge on others for a living; lead an idle or dissolute life.
to live as a hobo.
adjective,bum·mer,bum·mest.
Slang. of poor, wretched, or miserable quality; unsatisfactory: I figured $300 was a bum deal for a minor repair, but I paid it anyway.
Slang. fraudulent or fake: He was accused of issuing a bum check for $2920.
Slang. disappointing; unpleasant.
Slang. erroneous or ill-advised; misleading: I think the gauge is giving me a bum readout.
Slang. physically disabled, impaired, or injured: a bum leg.
Verb Phrases
bum around,Informal. to travel, wander, or spend one's time aimlessly: We bummed around for a couple of hours after work.
Idioms for bum
bum (someone) out, Slang. to disappoint, upset, or annoy: It really bummed me out that she could have helped and didn't.
on the bum, Informal.
living or traveling as or in a manner suggesting that of a hobo or tramp.
in a state of disrepair or disorder: The oven is on the bum again.
Origin of bum
1
An Americanism first recorded in 1860–65; perhaps a shortening of or back formation from bummer1; adjective senses of unclear relation to sense “loafer” and perhaps of distinct origin