"That comes from outside or from some external source; extrinsically added; extraneous; foreign", Early 17th cent.; earliest use found in Francis Bacon (1561–1626), lord chancellor, politician, and philosopher. From post-classical Latin adventivus (of a dowry) not derived from parents, of foreign origin from classical Latin advent-, past participial stem of advenīre + -īvus. Compare Middle French, French adventif.[adventive etymology, adventive origin, 英语词源]