"the domestic Bos taurus" (commonly meaning the castrated males, used to pull loads or for food), Middle English oxe, from Old English oxa "ox" (plural oxan), from Proto-Germanic *ukhson (source also of Old Norse oxi, Old Frisian oxa, Middle Dutch osse, Old Saxon, Old High German ohso, German Ochse, Gothic auhsa), from PIE *uks-en- "male animal," (source also of Welsh ych "ox," Middle Irish oss "stag," Sanskrit uksa, Avestan uxshan- "ox, bull"), said to be from root *uks- "to sprinkle," related to *ugw- "wet, moist." The animal word, then, is literally "besprinkler."
Also used from late Old English of the wild, undomesticated bovines. The black ox "misfortune, adversity, old age," etc., is by 1540s.
"having large, full eyes," 1620s, from ox + -eyed. An epithet used by Homer (boōpis) of the goddess Hera (Juno) and beautiful women. Oxeye has since c. 1400 been a name given to various flowering plants thought to resemble the eye of an ox; it is also used of certain birds, fishes, and a type of mirror.
also ox-bow, early 14c., ox-boue, "bow-shaped wooden collar for an ox," from ox + bow (n.1). Meaning "semicircular bend in a river" is from 1797, American English (New England), so called from the resemblance of the shape. The meaning "curved lake left after an oxbow meander has been cut off by a change in the river course" is from 1898.