From Old Norse 'hūsbōndi' (house-dweller): 'hūs' (house) + 'bōndi' (dweller/farmer). Originally meant householder, not married man. Replaced the native OE 'wer' (man), which survives only in 'werewolf'. 'Husbandry' preserves the original sense of managing a household.
From Old Norse 'hūsbōndi' (master of a house), composed of 'hūs' (house) and 'bōndi' (dweller, householder, farmer), from 'būa' (to dwell). A husband was originally not a married man but a householder — a man who owned and managed a dwelling. The marital meaning emerged because the head of a household was typically married. The Old Norse word replaced the native Old English
The Old English word for husband was 'wer' (man) — now extinct except in 'werewolf' (man-wolf). The Norse 'husband' replaced it. Meanwhile, 'husbandry' preserves the original meaning: managing a household or farm, not being married. And 'neighbor' is 'nēah-gebūr' (near-dweller) — the same root 'būa' (to dwell) that gives us the '-band' in husband.