8. bum Informal. to spend time or wander aimlessly.
9. (adj. Slang.)bum of poor or miserable quality; worthless.
10. bum disappointing; unpleasant.
11. bum false or misleading: a bum rap.
12. bum lame.
13. (Brit. Slang.)bum the buttocks.
Etymology: (1350–1400; ME bom)
Definition of 'bum'
Princeton's WordNet
1. (noun)rotter, dirty dog, rat, skunk, stinker, stinkpot, bum, puke, crumb, lowlife, scum bag, so-and-so, git a person who is deemed to be despicable or contemptible "only a rotter would do that"; "kill the rat"; "throw the bum out"; "you cowardly little pukes!"; "the British call a contemptible person a `git'"
2. (noun)tramp, hobo, bum a disreputable vagrant "a homeless tramp"; "he tried to help the really down-and-out bums"
3. (noun)idler, loafer, do-nothing, layabout, bum person who does no work "a lazy bum"
4. (adj)buttocks, nates, arse, butt, backside, bum, buns, can, fundament, hindquarters, hind end, keister, posterior, prat, rear, rear end, rump, stern, seat, tail, tail end, tooshie, tush, bottom, behind, derriere, fanny, ass the fleshy part of the human body that you sit on "he deserves a good kick in the butt"; "are you going to sit on your fanny and do nothing?"
5. (verb)bum, cheap, cheesy, chintzy, crummy, punk, sleazy, tinny of very poor quality; flimsy
6. (verb)mooch, bum, cadge, grub, sponge ask for and get free; be a parasite
7. (verb)bum, bum around, bum about, arse around, arse about, fuck off, loaf, frig around, waste one's time, lounge around, loll, loll around, lounge about be lazy or idle "Her son is just bumming around all day"
Definitions of bum 
Afrikaans: agterent, sitvlak
Arabic: عَجيزَه، كَفَل، مُؤَخَّرَ
Bulgarian: задник
Brazilian: bunda
Czech: zadek, zadnice
German: der Hintern
Danish: rumpe; bagdel; røv
Greek: πισινός
Spanish: culo, trasero
Estonian: taguots, kannikad
Farsi: نشیمنگاه
Finnish: takapuoli
French: cul
Hebrew: יַשְבָן
Hindi: गुमड़ा
Croatian: stražnjica
Hungarian: fenék
Indonesian: bokong
Italian: didietro
Japanese: 尻
Korean: 궁둥이
Lithuanian: užpakaliukas
Latvian: sēžamvieta; pakaļa
Malay: buntut
Dutch: gat
Norwegian: bak, rumpe
Polish: zadek
Persian: نشیمنگاه
Pashto: د كيناستو ځاى
Portuguese: rabo
Romanian: dos
Russian: зад(ница)
Slovak: zadok, prdelka
Slovenian: rit
Serbian: zadnjica
Swedish: rumpa,ända
Thai: ก้น
Turkish: kıç, göt
Taiwanese: 屁股
Ukrainian: зад
Urdu: چوٹر
Vietnamese: mông đít
Chinese: 屁股
