subjugate

The adjective is derived from Late Middle English subiugat(e), subjugat(e) (“made submissive; obedient”), the past participle of subiugaten, subjugaten (“to conquer; to subdue”), from Latin subiugātus, subjugātus (“subjugated”), the perfect passive participle of subiugō, subjugō (“to make subject, subjugate”), from sub- (prefix meaning ‘under’) + iugō, jugō (“to join; to yoke”) (from iugum (“collar for a horse; yoke for cattle”) (ultimately from Proto-Indo-European *yewg- (“to tie together, join, yoke”)) + -ō (suffix forming regular first-conjugation verbs)). Doublet of yoke. The noun is derived from the adjective.

From Late Middle English subiugate, subjugaten (“to conquer; to subdue”), from Latin subiugātus, subjugātus (“subjugated”): see further at etymology 1. The verb is attested slightly later than the adjective.