North America/US - A person who has little to no ambition to attempt to have as good a life as possible, i.e an unemployed and lazy type person who may still live with others and having somewhat of a locust lifestyle. Also a term used for a homeless person/tramp.

"Dude what you gonna do when your boss fires you? Live on the streets like a bum!?"

British/UK term - the ass/buttocks/butt is often referred to as a person's 'bum.'

US/North America - "Sit your butt down on that chair right there."

UK - "Sit on your bum on that chair right there."

Generally worldwide a bum is a term that's used to describe a typical douchebag, lazy and unambitious person.
"Dude you live at home with your parents and have no job or no girlfriend... You're a BUM!"
by Llewelyn Dowd March 28, 2022
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to borrow or beg something from another.
Usually when a friend asks to bum a cigarette you know he won't ever give a loosie back to you!
by talk2me-JCH2 July 17, 2022
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US/Canada
1. Pejorative for a homeless person, - especially one that makes no attempt to work or better himself (contrasted with the more respected working homeless “hobos”). Probably comes from the expression “lazy bums.”
Get a job you F’ing bum.

2. To shamelessly ask for something (in the manner of a bum – see above).
Dude can I bum a cigarette, five dollars, and a ride to the…

3. A loser with nothing going for him (no job, no aspirations etc). Especially an unworthy husband or boyfriend.
I can’t believe she’s with Jim. Always drinking, never workin, the guy is a bum.

UK/Commonwealth:
4. The more polite way of saying ass.
Does my bum look big in this?

5. To do in the bum.
I bummed a tart.

Afganistan
6. Bum is a major city in Afganistan.
I bummed a ride to Bum where I bummed a bum in his bum.
by author December 25, 2006
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To get something from someone else for free. Also used to borrow, but with the understanding that repayment might not happen.
by Tim March 13, 2003
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Someone who doesn't take care of their respective responsiblilities.

Someone who wants to live off you because they don't want to take care of themself. Someone who has nothing and does nothing to get something but expects it to fall into their lap.
K. Goodman is a 2nd class in the Navy and has nothing going for himself. He's a bum.
by CVSwirl November 16, 2014
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Someone who does nothing all day and expects everyone to bend over backwards to please them.

Someone who has no liscense, no car, no job, no girl.
Yo mike can you come scoop me up man and drive me around all day.
by darken one May 8, 2005
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Chris is a bum he sits in his moms back yard all day long with no ride or job.
Bum-some one who does nothing all day but expect people to bend over backwards.The first to have their hands out sits at home or in the streets all day bums usually don't have a place of their own no job,car,or money they think these things will fall out t of the sky.
by Bummed bummer bum bums February 8, 2014
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