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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 ) ( see defect) + -iōn- -ion

Explanation

Is your team so bad you have begun supporting a rival team? Then you're guilty of defection — the act of shifting your support to a new cause. Most people won't thank you for your defection. No matter how much you might believe in the new sports team, or political party, or whatever, defection is generally used as a critical term. Defection implies a lack of character — as you can tell by looking at its Latin roots, which come from the word defectionum, meaning "desertion, revolt, failure." Clearly, no one likes a defector.

Keep Reading on Vocabulary.com

Vocabulary lists containing defection

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.

That’s what the defection of his largest influencers portends.

From Salon • Apr. 10, 2026

Customer defection is of increasing concern for both airline management and shareholders, according to ASCI.

From MarketWatch • Apr. 6, 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

All three had written long, abject articles in the Times, analyzing the reasons for their defection and promising to make amends.

From "1984" by George Orwell