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Synonyms

defection

American  
[dih-fek-shuhn] / dɪˈfɛk ʃən /

noun

  1. desertion from allegiance, loyalty, duty, or the like; apostasy.

    His defection to East Germany was regarded as treasonable.
    Antonyms:
    loyalty

  2. failure; lack; loss.

    He was overcome by a sudden defection of courage.
defection British  
/ dɪˈfɛkʃən /

noun

  1. the act or an instance of defecting

  2. abandonment of duty, allegiance, principles, etc; backsliding

  3. another word for defect defect

"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

Other Word Forms

  • nondefection noun
  • redefection noun

Etymology

Origin of defection

1535–45; < Latin dēfectiōn- (stem of dēfectiō ), equivalent to dēfect ( us ) ( defect ) + -iōn- -ion

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Lowe, who represents Great Yarmouth in Norfolk, welcomed Whitford's defection on X, claiming "the patriots keep coming and coming".

From BBC • Feb. 20, 2026

Their sudden defection forced the SDF to withdraw from the Arab-majority provinces of Raqa and Deir Ezzor with little to no fighting and to retreat to Kurdish areas.

From Barron's • Feb. 20, 2026

The defection builds upon momentum Carney is building in public-opinion polls, as he steers a new course for the Canadian economy amid elevated uncertainty over U.S. trade policy and recent threats from President Trump.

From The Wall Street Journal • Feb. 18, 2026

Roddy's defection gives the Conservatives two councillors on the authority.

From BBC • Feb. 16, 2026

For the first time since his defection, he was plagued with doubts about the path his life had taken.

From "Spies: The Secret Showdown Between America and Russia" by Marc Favreau

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

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