"important arrival," 1742, an extended sense of Advent "season preceding Christmas" (in reference to the "coming" of Christ), late Old English, from Latin adventus "a coming, approach, arrival," in Church Latin "the coming of the Savior," from past participle stem of advenire "arrive at, come to," from ad "to" (see ad-) + venire "to come," from a suffixed form of PIE root *gwa- "to go, come." Related: Adventual.