1916, extravert (spelled with -o- after 1918, by influence of introvert), from German Extravert, from extra "outside" (see extra-) + Latin vertere "to turn" (see versus). Used (with introvert) in English by doctors and scientists in various literal senses since 1600s, but popularized in a psychological sense early 20c. by Carl Jung. Related: Extroverted.[extrovert etymology, extrovert origin, 英语词源]