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nadie (Indefinite Pronoun) "no one"
12th cent. Old Spanish nadi. The shift from -i to -ie was under influence of Old Spanish otri, otrie, otrien "somebody else" (see also otro). From Latin nati 'id.,' part of a larger phrase homines nati "no one" (but lit. "men born"), from an ancient Latin expression homines nati non fecerunt "born men did not do it." According to Malkiel (1945), use of the phrase was endemic to central Iberia.
Old Spanish nade "no one," naide 'id.,' naiden 'id.'
Old Aragonese nadi, Old Leonese nadi, Ladino naidi