From Middle English mishapnen, equivalent to mis- + happen.
mishappen (third-person singular simple present mishappens, present participle mishappening, simple past and past participle mishappened)
- (obsolete) To encounter grief or misfortune.
- (now rare) To happen through misfortune.
1590, Edmund Spenser, “Book I, Canto III”, in The Faerie Queene. […], London: […] [John Wolfe] for William Ponsonbie, OCLC 960102938:
His fearefull friends weare out the wofull night, / Ne dare to weepe, nor seeme to vnderstand / The heauie hap, which on them is alight, / Affraid, least to themselues the like mishappen might.
- (intransitive) To happen ill; fare ill.