Ox
A grown castrated male trained for draught work; also an old word for any bovine.
Also: oxen, draught ox
An ox is usually a mature castrated male that has been trained to pull loads, ploughs or carts, often working from about four years old. Oxen are slower than horses but strong, steady in mud and cheap to feed, and for thousands of years they did most of the heavy farm work of Europe, Asia and Africa. They are worked in pairs or teams under a yoke and guided by voice, goad and, in South Asia, a nose rope. In zoology the word is wider: Bos is the ox genus, and wild cattle such as the aurochs, gaur and banteng are called wild oxen. The plural is oxen.