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" (from PIE root *med- "take appropriate measures"). 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 (in contrast to ancient; in contrast to traditional by 1930s); modern dance first attested 1912; first record of modern jazz is from 1954. Modern conveniences first recorded 1926.