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idiota (Adjective, Noun) "idiotic;" "idiot"

13th cent. From Latin idiota 'id.,' borrowed from Greek ἰδιώτης (idiótes) "uneducated person," "commoner." From ἴδιος (ídios) "private." From Proto-Indo-European *su̯o-i̯o- "ourself." Developed from the reflexive pronoun *su̯e- (see se (1)).