The definition of overweening is someone who is arrogant or has excessive pride and confidence.(adjective)
Someone who brags that he is the best tennis player in the world and claims he can beat all rivals when that's unlikely to be true is an example of someone who would be described as overweening.
See overweening in Webster's New World College Dictionary
Origin: ME oferweninge, prp. of oferwenen < OE oferwenan: see over- & ween
See overweening in American Heritage Dictionary 4
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