wīf

Wife comes from Old English wīf, which meant simply 'woman' or 'female person,' regardless of marital status. The Proto-Germanic source was *wībą, whose deeper etymology is uncertain — some linguists connect it to a root meaning 'to veil' or 'to wrap,' but this is speculative. In Old English, a married woman was a wīf in the same way that an unmarried woman was a wīf. The word did not specify a relationship.

The compound 'wīfmann' (woman-person) existed alongside wīf for centuries. Over time, wīfmann contracted into 'woman,' and wīf narrowed from 'any female person' to 'a married female person.' The narrowing was gradual — thirteenth-century texts use wīf in both senses. By the fifteenth century, the narrowing was nearly complete. 'Woman' had absorbed the general meaning. 'Wife' kept only the marital one.

The word's original meaning survives in compounds that predate the narrowing. A midwife is a 'with-woman' — a woman who is present at childbirth. A fishwife is a woman who sells fish. An alewife sold ale. A housewife keeps the house. In none of these compounds does 'wife' mean 'married woman.' It means 'woman.' The compounds are linguistic fossils, preserving a meaning the standalone word has lost.

The plural 'wives' follows Old English patterns of f-to-v voicing (knife/knives, life/lives). This voicing pattern, which dates to Proto-Germanic, is one of the oldest grammatical features still active in modern English. Every time someone says 'wives,' they are producing a sound change that occurred before English existed as a distinct language.