1916, Amer.Eng., "stupid person," perhaps a variant of Eng. dial. goff "foolish clown" (1869), from 16c. goffe, probably from M.Fr. goffe "awkward, stupid," of uncertain origin. Or Eng. goffe may be from M.E. goffen "speak in a frivolous manner," possibly from O.E. gegaf "buffoonery," and gaffetung "scolding." Sense of "a blunder" is c.1954, probably infl. by gaffe. The verbal meaning "waste time" is 1932; the verb meaning "make a mistake" is from 1941. Goof off "loaf" is also from 1941. Adj. goofy is attested from 1921. The Disney character of that name began life as Dippy Dawg c.1929. Goofball "narcotic" is from 1938; as an intensive of goof, it dates from 1959.
The Dictionary of American Slang, Fourth Edition by Barbara Ann Kipfer, PhD. and Robert L. Chapman, Ph.D. Copyright (C) 2007 by HarperCollins Publishers. Cite This Source
Idioms and Phrases with goof up
Blunder, make a mistake, spoil. For example, I really goofed up and got all the dates wrong. This expression emerged in the military during World War II, along with the synonymous goof off. Quite often up is omitted, as in Sorry, I goofed.
[ ; c. 1940