Source : Webster's Revised Unabridged Dictionary (1913)

Misstep \Mis*step"\, n.
   A wrong step; an error of conduct.

Misstep \Mis*step"\, v. i.
   To take a wrong step; to go astray.

Source : WordNet®

misstep
     n : an unintentional but embarrassing blunder; "he recited the
         whole poem without a single trip"; "he arranged his robes
         to avoid a trip-up later"; "confusion caused his
         unfortunate misstep" [syn: {trip}, {trip-up}, {stumble}]