Origin of goof

1915–20; apparently variant of obsolete goff dolt < Middle French goffe awkward, stupid
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for goof on

goof

noun

a foolish error or mistake
a stupid person

verb

to bungle (something); botch
(intr; often foll by about or around) to fool (around); mess (about)
(tr) to dope with drugs
(intr often foll by off) US and Canadian to waste time; idle

Word Origin for goof

C20: probably from (dialect) goff simpleton, from Old French goffe clumsy, from Italian goffo, of obscure origin
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for goof on

goof

v.

"waste time," 1932; "make a mistake," 1941, from goof (n.). Goof off "loaf" is also from 1941. Related: Goofed; goofing.

goof

n.

1916, American English, "stupid person," perhaps a variant of English dialect goff "foolish clown" (1869), from 16c. goffe, probably from Middle French goffe "awkward, stupid," of uncertain origin. Or English goffe may be from Middle English goffen "speak in a frivolous manner," possibly from Old English gegaf "buffoonery," and gaffetung "scolding." Sense of "a blunder" is c.1954, probably influenced by gaffe.

Online Etymology Dictionary, © 2010 Douglas Harper

Idioms and Phrases with goof on

goof on

Make fun of, mock, as in He was always goofing on his little brother. [Slang; mid-1900s]

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.