An archaic or obsolete form meaning to make disquieted; to disturb or trouble someone.
From disquiet + -en (archaic causative suffix). The -en suffix appears in Old English verbs like 'darken' and 'deafen' to create verbs meaning 'to make' or 'to become.'
The -en suffix created causative verbs in older English—'disquieten' means 'to make disquiet,' much like 'frighten' means 'to make afraid.' It's mostly replaced by phrases using 'make' now.
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