The Collaborative International Dictionary of English v.0.48:

Misspeak \Mis*speak"\, v. i.
   To err in speaking.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Misspeak \Mis*speak"\, v. t.
   To utter wrongly.
   [1913 Webster]

WordNet (r) 3.0 (2006):

misspeak
    v 1: pronounce a word incorrectly; "She mispronounces many
         Latinate words" [syn: mispronounce, misspeak]