"Oxen" is one of only three commonly used English words to still use the "-en" plural. The others are "children" and "brethren" (fellow Christians or members of a male religious order, though the modern form "brothers" is used for biological brothers).

An ox, also known as a bullock in Australia and India, is a bovine trained as a draft animal. Oxen are commonly castrated adult male cattle; castration makes the animals easier to control. Cows (adult females) or bulls (intact males) may also be used in some areas.

Oxen are used for plowing, for transport (pulling carts, hauling wagons and even riding), for threshing grain by trampling, and for powering machines that grind grain or supply irrigation among other purposes. Oxen may be also used to skid logs in forests, particularly in low-impact, select-cut logging.

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