goof

Short definition from Wiktionary

Noun

1. 1
   A mistake or error.
2. 2
   A mistake or error: An error made during production which finds its way into the final release.
3. 3
   A foolish and/or silly person; a goofball.
4. 4
   A rapist.

Verb

1. 1
   To make a mistake.
2. 2
   To engage in mischief.