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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

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.

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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.

See Examples For:

It is the first known defection of a North Korean soldier since last October.

From The Wall Street Journal Jun. 24, 2026

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

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

“I think we should continue the current romance. A quick defection from Peeta could cause the audience to lose sympathy for her,” says Plutarch.

From "Mockingjay" by Suzanne Collins

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