The basic meaning of the prefix mis- is “bad; badly; wrong; wrongly.” Thus misfortune means “bad fortune” and misbehave means “to behave badly.” Likewise, a misdeed is “a wrong deed” and misdo means “to do wrongly.” Mis- forms compounds primarily by attaching to verbs: mishear, misremember. Mis- also frequently forms compounds by attaching to nouns that come from verbs: miscalculation, mismanagement, mispronunciation. The prefix mis- can be traced back to Old English. Another mis- is a variant of miso-, discussed below.
