The definition of presumptuous is taking things for granted or being overconfident.(adjective)
An example of presumptuous is assuming that you will win the city wide spelling bee just because you scored 100% on your last spelling quiz.
See presumptuous in Webster's New World College Dictionary
Origin: ME < OFr presunteux < LL praesumptuosus < L praesumptus: see presumption
See presumptuous in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old French presumptueux
Origin: , from Late Latin praesūmptuōsus
Origin: , variant of praesūmptiōsus
Origin: , from praesūmptiō, presumption; see presumption.
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