mendacity

Etymology

From Late Latin mendacitas, from Latin mendāx (“deceitful, deceptive, lying”) + -itās (suffix forming nouns indicating a state of being). Mendāx is derived from mentior (“to deceive, lie”) (from mēns, mentis (“mind; intellect; judgment, reasoning”), from Proto-Indo-European *méntis (“thought”)) + -āx (suffix forming adjectives expressing a tendency or inclination), or from Proto-Indo-European *mend- (“to fault”). By surface analysis, Latin mendāc- + -ity.