At-stud

a studhorse or stallion.
an establishment, as a farm, in which horses are kept for breeding.
a number of horses, usually for racing or hunting, bred or kept by one owner.
a male animal, as a bull or ram, kept for breeding.
a herd of animals kept for breeding.
Slang. a man, especially one who is notably virile and sexually active.
Poker. .
of, associated with, or pertaining to a studhorse or studhorses.
retained for breeding purposes.
at / in stud, (of a male animal) offered for the purpose of breeding.
noun
a large-headed nail or other projection protruding from a surface, usually as decoration
a type of fastener consisting of two discs at either end of a short shank, used to fasten shirtfronts, collars, etc
(building trades) a vertical member made of timber, steel, etc, that is used with others to construct the framework of a wall
a headless bolt that is threaded at both ends, the centre portion being unthreaded
any short projection on a machine, such as the metal cylinder that forms a journal for the gears on a screw-cutting lathe
the crossbar in the centre of a link of a heavy chain
one of a number of rounded projections on the sole of a boot or shoe to give better grip, as on a football boot
verb (transitive) studs, studding, studded
to provide, ornament, or make with studs
to dot or cover (with): the park was studded with daisies
(building trades) to provide or support (a wall, partition, etc) with studs
noun
a group of pedigree animals, esp horses, kept for breeding purposes
any male animal kept principally for breeding purposes, esp a stallion
a farm or stable where a stud is kept
the state or condition of being kept for breeding purposes: at stud, put to stud
(modifier) of or relating to such animals or the place where they are kept: a stud farm, a stud horse
(slang) a virile or sexually active man
short for stud poker
n.

“nailhead, knob,” Old English studu “pillar, prop, post,” from Proto-Germanic *stud- (cf. Old Norse stoð “staff, stick,” prop. “stay,” Middle High German stud, Old English stow “place”), from PIE *stu-, variant of root *sta- “to stand” (see stet). Sense expanded by late 14c. to include ornamental devices fixed in and projecting from a surface. The verb is c.1500 in the literal sense of “set with studs,” 1560s in studded with “as though sprinkled with nails with conspicuous heads.”

“horse used for breeding,” Old English stod “herd of horses, place where horses are kept for breeding,” from Proto-Germanic *stodo (cf. Old Norse stoð, Middle Low German stod, Old High German stuot “herd of horses,” German Stute “mare”), from PIE root *sta- “to stand,” with derivatives meaning “place or thing that is standing” (cf. Old Church Slavonic stado “herd,” Lithuanian stodas “a drove of horses;” see stet). Sense of “male horse kept for breeding” is first recorded 1803; meaning “man who is highly active and proficient sexually” is attested from 1895; that of “any young man” is from 1929.

adjective

Haughty and conceited; snobbish; hincty: We didn’t like her at first because we thought she acted stuck-up (1839+)