Do people even know what they’re saying? I took four years of high school French and still had to look this shit up. n."woman to whom one is betrothed," 1853, from French fianceé, fem. offiancé, past participle of fiancer "to betroth," from fiance "a promise, trust," from fier "to trust." Has all but expelled native betrothed. The verb fiance, now obsolete, was used c.1450-1600 for "to engage to be married."