"outgoing, overtly expressive person," 1916, extravert (spelled with -o- after 1918, by influence of introvert), from German Extravert, from extra "outside" (see extra-) + Latin vertere "to turn" (from PIE root *wer- (2) "to turn, bend"). 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.