mid-15c. (mid-14c. as overweenende, with the earlier ending), present-participle adjective from verb overwenen "be conceited or arrogant, think too highly or confidently (especially of oneself); be presumptuous, be over-confident" (mid-14c.), from over- + ween or else from Old English oferwenian "to be proud, become insolent or presumptuous." Middle English also had overwēne (n.) "presumption, arrogance" (mid-13c.); overwēnere "one who is presumptuous or arrogant."
It forms all or part of: vanadium; Vanir; venerate; veneration; venerable; venereal; venery (n.1) "pursuit of sexual pleasure;" venery (n.2) "hunting, the sports of the chase;" venial; venison; venom; Venus; wean; ween; Wend "Slavic people of eastern Germany;" win; winsome; wish; wont; wynn.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit veti "follows after," vanas- "desire," vanati "desires, loves, wins;" Avestan vanaiti "he wishes, is victorious;" Latin venerari "to worship," venus "love, sexual desire; loveliness, beauty;" Old English wynn "joy," wunian "to dwell," wenian "to accustom, train, wean," wyscan "to wish."