A pen is an enclosure for domestic animals. Most common types of pens are pigpens, horse paddocks, cattle pens, and sheep pens.
A large pen for horses is called a paddock (USA, UK) or a corral (Western USA), a borrowing from the Spanish language. A small pen for horses (no more than 15-20 feet on any side) is a stall if inside a barn or stable, or simply a "pen" if it lacks any roof or shelter. A large fenced field is called a "pasture," or, in some cases, "rangeland."
A cattle pen is also sometimes called a corral.
In Australia and New Zealand a pen is a small enclosure for livestock (especially sheep or cattle), which is part of a larger construction, eg. calf pen, forcing pen (or yard) in sheep or cattle yards, or a sweating pen or catching pen in a shearing shed. In Australia, a "paddock" may encompass a large, fenced grazing area of many acres, not to be confused with the American English use of "paddock" as interchangable with "corral" or "pen," describing smaller, confined areas.
A sheep pen is also called a folding, sheepfold or sheepcote. Modern shepherds more commonly use terms such as closing or confinement pen for small sheep pens. Most structures today referred to as sheepfolds are ancient dry stone semicircles.
Constructions of pens vary, depending on purpose, animal type, and culture. Primitive pens in South Africa are called kraal.
References"Macquarie Dictionary, The", 2nd edition, 1991
sheepcote in Hebrew: דיר
sheepcote in Hungarian: Karám (néprajz)