The definition of a goof is a silly person, or an accidental mistake.(noun)
To goof is defined as to make a mistake, or to do something to waste time, usually used with "up" or "off."(verb)
See goof in Webster's New World College Dictionary
Origin: prob. < dial. goff < Fr goffe, stupid < It goffo
See goof in American Heritage Dictionary 4
Origin: Possibly alteration of dialectal goff, fool
Origin: , from obsolete French goffe, stupid.
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