зад buttocks, rump, butt, ass

buttocks
Мне не нравится её юбка — она обтягивает зад. I don't like her skirt: it strains across the buttocks.
rump
отвислый зад a droopy rump
butt
Мужик, а зад у него бабий. He's got a butt on him like a woman.
ass
Идёт и виляет задом, бесстыдница. She swings her ass when she walks, the shameless hussy.

Semantics

This entry is concerned with the use of the word зад to refer to human buttocks and to the rear part of an animal. Common sense will dictate which of the expressions in this entry can or cannot be used to refer to animals or humans. The meaning "rear part of an object," e.g. зад повозки "tail of a wagon," is not described in this dictionary.

Morphology

зад SE Loc. (в/на) -у; m.in.noun

Syntax

Syntactic actants

Actant 1: whose buttocks they are
(a) Genitive not Common
(b) Possessive
Толстый зад нашего учителя не помещался на стуле. Our teacher's fat ass wouldn't fit in the chair.
Тётка заслонила проход своим широким задом. The woman blocked the way with her big wide ass.
NB When the word зад functions as a subject and has no descriptive modifier, the construction зад у + Genitive is often preferred to (a) and (b), above:
Зад у Петьки был худой и костлявый. Pet'ka had a skinny, bony butt.

Lexical Relationships

Synonyms

задница Rude ass; asshole
NB The word задница is more vulgar than зад. It may be used as an epithet, e.g. Ах ты, задница! "You asshole!" The word зад is not used in such expressions. Thus there are also no neutral adjectives used with задница, while there are such used with зад, e.g. круглый зад "a rounded butt," худой зад "a skinny butt."
попа Colloquial; попка Colloquial bottom
NB The words попа and попка are usually used to refer to that part of a child's anatomy:
Вытри попу! Wipe your bottom!
жопа Vulgar ass
сиденье Euphemistic seat
седалище Jocular, Euphemistic derriеre
ягодицы; ягодицы buttocks

Diminutives

задик butt, ass
Посмотри, какой у неё аккуратный, подтянутый задик. Look what a neat, firm butt she has.

Augmentatives

задище ass

Parts

ягодица; ягодица buttock
левая ягодица left buttock
правая ягодица right buttock

Size and shape

большой зад a large butt
огромный зад; необъятный зад Ironic an enormous butt
широкий зад a wide butt
бабий зад an effeminate butt
NB The above expression is used to describe a man with wide buttocks.
толстый зад a plump butt
жирный зад a fat butt
худой зад; худощавый зад a skinny butt
костлявый зад a bony butt
круглый зад a rounded butt
отвислый зад a droopy rump
NB The above expression is often used to describe a horse's rump.
оттопыренный зад a protruding butt
плоский зад a flat butt
тяжёлый зад a heavy butt
подтянутый зад a firm butt
аккуратный задик a neat little butt

Inflicting injuries

давать/дать Nd по задуd;
наподдавать/наподдать Nd в задa 		to give N a slap/kick on the butt
За такие штучки ему надо дать по заду! You ought to give him a slap on the butt for those sorts of antics!
шлёпать/нашлёпать, отшлёпать Na to spank N
Мальчишка плохо себя вёл, и мать нашлёпала его. The kid misbehaved, and his mother spanked him.
давать/дать Nd коленкойi под задa to knee N in the butt

Movements

вилять [no Pf.] задомi to swing, to swish one's butt
Ну и походка у него! Виляет задом, как проститутка! Look at the way he walks! He swings his butt like a prostitute!
вскидывать/вскинуть задомi;
бить/забить [Pf-begin] задомi 		to buck
NB The above two expressions are usually used to describe movements of a horse.
подбрасывать [no Pf.] задa to bounce one's rump
садиться/сесть на задa to sit on one's haunches
NB The above two expressions are usually said of an animal.
хлопать/похлопать Na по задуd;
шлёпать/пошлёпать Na по задуd 		to slap N's behind
NB The above two expressions refer to a gesture that is often interpreted as condescending or as a crude pass at a woman.

Clothing

обтягивать [no Pf.]: Nn обтягивает задa N strains across one's buttocks
NB N denotes clothing.
спадать [no Pf.]: Nn спадает с задаg N is hanging off one's buttocks
NB N denotes clothing.
висеть [no Pf.]: Nn висит на задуloc;
болтаться [no Pf.]: Nn болтается на задуloc 		N hangs on one's buttocks
NB N denotes clothing.

Sample texts

Он страшно похудел, штаны болтаются (or висят) на заду. He lost a lot of weight, and now his pants just hang on his buttocks.
Пиратка садился на зад, подняв передние ноги на воздух. [А. Куприн, Пиратка] Piratka would sit up with his front paws raised. [A. Kuprin, "Piratka"]
Волк бежал не очень быстро, мелко перебирая лапами, подбрасывая худощавый зад и часто косясь на Романа. [Ю. Сорокин, Роман] The wolf was running fairly slowly, with short, careful steps, bouncing his skinny rump and frequently glancing back at Roman. [Yu. Sorokin, Roman]