overween
To think too highly or arrogantly of (oneself).
and they that overween, / And at thy growing virtues fret their spleen,
To make or render arrogant and overweening.
There is, I suppose, the cheap drama of man sticking his nose into an area where it does little good except to expand his already overweened vanity.
To overwhelm.
The invasion of a vast enemy host upon the unprepared is unstoppable; the huge phalanx of tanks overweens our small army of trucks and rifles; […]
Where it comes from
From Middle English overwēnen (“to be presumptuous, be over-confident; presume”), from Old English oferwennan and oferwenian (“to be proud, become insolent, or presumptuous”), equivalent to over- + ween.
Adapted from the Wiktionary entry overween (CC BY-SA 4.0).