• synonyms


verb (used with or without object), interjection
  1. fuck: Stop effing around and get to work! Eff you, you lout!
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  1. the word “fuck”; the f-word: peppering his speech with superfluous and highly offensive effs.
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Verb Phrases
  1. eff off, Go away!: Eff off and die, you piece of Martian scum!
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Origin of eff

1940–45; euphemism for fuck, with eff as spelled form of the name of the initial letter


  1. efficient, efficiency.
  2. effective, effectiveness.
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Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for eff

Contemporary Examples

Historical Examples

  • Then he blew into the "eff" holes; and wetting his finger he rubbed the varnish.

    Abe and Mawruss

    Montague Glass

  • An' eff he don't feel the sperit ter pray, he won't pray, an' I hev got ter surroun' the throne o' grace by myself.

  • She had a little maid who attended her,—Eff she called her,—and the girl stood by to watch while Anne did my bidding.

  • So I got the tackle of Eff's father—rude enough it was in all conscience—and in the early afternoon I set out to the sport.

  • Then she stopped exhausted, smiled on Eff, who sat like a cinder-witch all the while, and smoothed the hair from her brow.

British Dictionary definitions for eff


  1. euphemism for fuck taboo eff off
  2. eff and blind slang to use obscene language
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Derived Formseffing, noun, adjective, adverb
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 eff

1943, euphemism for fuck, representing the sound of its first letter. Related: Effing.

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Online Etymology Dictionary, © 2010 Douglas Harper