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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

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

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

It is possible these swings were all coincidental.

From Barron's • Feb. 23, 2026

What’s happening in the world isn’t a series of coincidental, unrelated events.

From The Wall Street Journal • Jan. 14, 2026

Even though it seemed awfully coincidental, I didn’t want to push my luck by asking too many questions about who this someone was.

From "The Glass Castle" by Jeannette Walls

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.