What's the difference between i.e. and e.g.?
1530s, "turn (something) to foolishness, frustrate," from Latin infatuatus, past participle of infatuare "make a fool of," from in- "in" (see in- (2)) + fatuus "foolish." Specific sense of "inspire (in someone) a foolish romantic passion" is from 1620s. Related: Infatuated; infatuating.