misadventure (n.)

"an unfortunate experience, a bad experience, ill-luck, calamity," c. 1300, misaventure, from Old French mesaventure (12c.) "accident, mishap," from mesavenir "to turn out badly;" see mis- (2) + adventure (n.) in the older sense of "that which happens by chance, fortune, luck." The spelling with -d- became regular after c. 1600.