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definitions

back formation

noun Linguistics.
  1. the analogical creation of one word from another word that appears to be a derived or inflected form of the first by dropping the apparent affix or by modification.
  2. a word so formed, as typewrite from typewriter.

Origin of back formation

First recorded in 1885–90
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for back-formation

back formation

noun
  1. the invention of a new word on the assumption that a familiar word is derived from it. The verbs edit and burgle were so created from editor and burglar
  2. a word formed by this process
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 back-formation
n.

also back formation, by 1887, from back (adv.) + formation.

Online Etymology Dictionary, © 2010 Douglas Harper