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c.1500, "now existing;" 1580s, "of or pertaining to present or recent times;" from Middle French moderne (15c.) and directly from Late Latin modernus "modern" (Priscian, Cassiodorus), from Latin modo "just now, in a (certain) manner," from modo (adv.) "to the measure," ablative of modus "manner, measure" (see mode (n.1)). Extended form modern-day attested from 1909.
In Shakespeare, often with a sense of "every-day, ordinary, commonplace." Slang abbreviation mod first attested 1960. Modern art is from 1807 (by contrast to ancient); modern dance first attested 1912; first record of modern jazz is from 1954. Modern conveniences first recorded 1926.
1580s, "person of the present time" (contrasted to ancient, from modern (adj.). From 1897 as "one who is up to date."