1375-1425;late Middle English (south); replacing earlier fixen,Middle English (north), for Old Englishfyxe, feminine of foxfox (compare fyxen (adj.) pertaining to a fox, Old High Germanfuhsin (noun) vixen)
O.E. *fyxen (implied in adj. fyxan), fem. of fox (see fox, and cf. M.H.G. vühsinne, Ger. füchsin). Solitary English survival of the Germanic feminine suffix -en, -in (cf. O.E. gyden "goddess;" mynecen "nun," from munuc "monk;" wlyfen "she-wolf"). The fig. sense "ill-tempered woman" is attested from 1575. The spelling shift from -f- to -v- began late 1500s (see V).