One of the earliest animals to be domesticated for agricultural purposes, sheep are primarily valued for their fleece and meat. A sheep's wool is the most widely used of any animal, and is typically harvested by shearing. Ovine meat is called lamb when from younger animals and mutton when from older ones. They continue to be important for wool and meat today, and are also occasionally raised for pelts, as dairy animals, or as model organisms for science.

Sheep husbandry is practiced throughout the inhabited world, and has played a pivotal role in many civilizations. In the modern era, Australia, New Zealand, Patagonian nations, and the United Kingdom are most closely associated with sheep production. Sheep-raising has a large lexicon of unique terms which vary considerably by region and dialect. Use of the word sheep began in Middle English as a derivation of the Old English word scēap; it is both the singular and plural name for the animal. A group of sheep is called a flock, herd or mob. Adult female sheep are referred to as ewes, intact males as rams, castrated males as wethers, and younger sheep as lambs. Many other specific terms for the various life stages of sheep exist, generally related to lambing, shearing, and age.

Being a key animal in the history of farming, sheep have a deeply entrenched place in human culture, and find representation in much modern language and zymology. As livestock, sheep are most-often associated with pastoral, Arcadian imagery. Sheep figure in many mythologies—such as the Golden Fleece—and major religions, especially the Abrahamic traditions. In both ancient and modern religious ritual, sheep are used as sacrificial animals. In contemporary English language usage, people who are timid, easily led, or stupid are often compared to sheep.

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