1. (noun)rear, backside, back end the side of an object that is opposite its front "his room was toward the rear of the hotel"
2. (noun)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 humanbody that you sit on "he deserves a good kick in the butt"; "are you going to sit on your fanny and do nothing?"
Definition of 'backside'
Webster Dictionary
1. (noun)backside the hinder part, posteriors, or rump of a person or animal
Definitions of backside 
Afrikaans: bas, alie
Arabic: مُؤَخَّره، كفَل
Bulgarian: задни части
Brazilian: traseiro
Czech: zadek, prdel (vulg.)
German: das Hinterteil
Danish: bagdel; ende
Greek: οπίσθια
Spanish: trasero, nalgas, posadera
Estonian: tagumik
Farsi: نشیمنگاه؛ کپل
Finnish: takapuoli
French: derrière
Hebrew: יַשׁבָן
Hindi: पीछे का हिस्सा
Croatian: stražnjica
Hungarian: fenék
Indonesian: bokong, pantat
Icelandic: rass, sitjandi
Italian: didietro
Japanese: 尻
Korean: 후부
Lithuanian: užpakalis
Latvian: pakaļpuse; sēžamvieta
Malay: punggung
Dutch: achterwerk
Norwegian: bak, rumpe
Polish: tyłek
Persian: نشیمنگاه؛ کپل
Portuguese: traseiro
Romanian: partea din spate/din fund
Russian: задница
Slovak: zadok
Slovenian: zadnja plat
Serbian: zadnjica
Swedish: bak,ända
Thai: ก้นหรือบั้นท้าย
Turkish: kıç, popo
Taiwanese: 臀部
Ukrainian: зад; сідниці
Urdu: چُوتڑ
Vietnamese: mông đít
Chinese: 屁股，臀部
