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Synonyms

coincidental

American  
[koh-in-si-den-tl] / koʊˌɪn sɪˈdɛn tl /

adjective

  1. happening by or resulting from coincidence; by chance.

    a coincidental meeting.

  2. existing or occurring at the same time.


coincidental British  
/ kəʊˌɪnsɪˈdɛntəl /

adjective

  1. of or happening by a coincidence; fortuitous

"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

  • coincidentally adverb
  • coincidently adverb
  • noncoincidental adjective
  • noncoincidentally adverb
  • uncoincidental adjective
  • uncoincidentally adverb

Etymology

Origin of coincidental

First recorded in 1790–1800; coincident + -al 1

Explanation

Things that are coincidental take place at the same time, but there isn't any connection. It's just chance — a coincidence. Sometimes things seem connected because they happen at the same time, but they really aren't: they're just coincidental. A sports fan might have a lucky shirt he wears to bring his team luck. But, if his team wins, that's just coincidental. Shirts, unfortunately, don't influence game outcomes. Coincidental is the opposite of causal, which means one thing directly causing another to happen. When coincidental things happen — like a friend calls just when you were thinking of her — it's just luck or chance.

Keep Reading on Vocabulary.com

Vocabulary lists containing coincidental

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.

"Underlying or concurrent illnesses may be responsible, or the events could be coincidental," it added.

From BBC • Mar. 8, 2026

Patel, an avid hockey fan, has defended the trip, arguing that the timing was coincidental with meetings he had been planning to attend with the FBI’s European counterparts.

From The Wall Street Journal • Mar. 2, 2026

Owens is maximalist in her approach, tossing out anything that to her seems funky or confusing or too coincidental, even when they lead to theories that contradict one another.

From Slate • Feb. 27, 2026

That synchronicity was too frequent to be coincidental.

From Science Daily • Oct. 22, 2025

Skeptics argue coincidental alignment and the conventional Hubble-Humason interpretation of the red shift.

From "Cosmos" by Carl Sagan