Definition of goof-up:
(n) :
(US, informal) A mistake or error.
(v) :
(US) To make a mistake.
(v) :
(US) To engage in mischief.
(n) :
(US, Canada, MTE, informal) A foolish and/or silly person; a goofball.
(n) :
(US, cinematography, informal) An error made during production which finds its way into the final release.
(n) :
(Canada, prison slang) A rapist.