ac·​ci·​den·​tal | \ ˌak-sə-ˈden-tᵊl How to pronounce accidental (audio) \

Definition of accidental

 (Entry 1 of 2)

1a : occurring unexpectedly or by chance an accidental discovery Their meeting was purely accidental.
b : happening without intent or through carelessness and often with unfortunate results The death was ruled accidental.
2 : arising from extrinsic causes : incidental, nonessential
3 of a bird : appearing outside its normal geographic range, migration route, or season



Definition of accidental (Entry 2 of 2)

1 : a nonessential property
2a music : a note foreign to a key indicated by a signature
b : a prefixed sign indicating an accidental
3 : a bird found outside its normal geographic range, migration route, or season : vagrant

Other Words from accidental


accidentalness \ ˌak-​sə-​ˈden-​tᵊl-​nəs How to pronounce accidental (audio) \ noun

Choose the Right Synonym for accidental


accidental, fortuitous, casual, contingent mean not amenable to planning or prediction. accidental stresses chance. any resemblance to actual persons is entirely accidental fortuitous so strongly suggests chance that it often connotes entire absence of cause. a series of fortuitous events casual stresses lack of real or apparent premeditation or intent. a casual encounter with a stranger contingent suggests possibility of happening but stresses uncertainty and dependence on other future events for existence or occurrence. the contingent effects of the proposed law

Frequently Asked Questions About accidental

What is the difference between accidental and incidental?

Accidental describes what was not planned or intended. It means "happening by accident" or "happening as an accident," as in "an accidental discovery" and "an accidental injury." Incidental typically means "happening as a minor part or result of something else," as in "a chapter that is incidental to the novel's plot." For more information read the full article.

Do you say 'on accident' or 'by accident'?

While both "by accident" and "on accident" are used, "by accident" is far more common.

What does 'accident waiting to happen' mean?

The phrase "an accident waiting to happen" refers to a person or thing that is dangerous or unsafe. For example, a very clumsy person and a rickety ladder might both be referred to as "an accident waiting to happen."

Examples of accidental in a Sentence

Adjective an accidental discovery of oil The timing of the announcement was purely accidental. The death was ruled accidental.
Recent Examples on the Web: Adjective Encounters with fentanyl can also be accidental as dealers combine it with stimulants, said Nora Volkow, director at the National Institute on Drug Abuse. Jon Kamp, WSJ, 11 May 2022 Travis Foster originally told police that the shooting was accidental. Olivia Mitchell, cleveland, 6 May 2022 Some of the world's greatest discoveries were accidental, such as penicillin, plastic and gunpowder. Nuala Walsh, Forbes, 4 May 2022 Plus, the durable cover will protect her hard work from any accidental water bottle spills. Samantha Lawyer, Woman's Day, 27 Apr. 2022 From kids to pets to accidental spills, keeping your couch clean can be quite a task. Kaylei Fear, Better Homes & Gardens, 17 Nov. 2021 The barely-there invisible liner is waterproof, repelling liquids, bodily fluids, and accidental spills. Amy Schulman,, 19 Sep. 2021 Unexplained fires at strategic locations in Russia, including a sensitive defense research site and the country’s largest chemical plant, have raised suspicions of some kind of sabotage despite no evidence that most were not accidental. Washington Post, 27 Apr. 2022 Cella’s comments clarify that all these Moon Knight Easter eggs aren’t accidental. Chris Smith, BGR, 26 Apr. 2022 Recent Examples on the Web: Noun The county sheriff ruled Rishell’s death accidental, and her family had remained close with Harold. Rachel Monroe, Outside Online, 16 Oct. 2018 After Saget's family shared their statement, the medical examiner also released their findings, ruling Saget's death accidental. Greta Bjornson,, 16 Feb. 2022 Of those, 15 were deemed justifiable and one accidental. Carol Robinson |, al, 6 Dec. 2021 Ocean City officials had stated that a medical examiner ruled O’Connor’s death accidental, caused by asphyxia due to suffocation., 26 May 2021 Lydia Cisaruk, Le Petite Academy’s director of communications, said the vehicle was driven by a school family member and called the crash accidental. Andrew J. Campa, Los Angeles Times, 22 Feb. 2021 Of those, 15 were ruled justifiable and one accidental and therefore not deemed criminal. Carol Robinson |, al, 4 Jan. 2021 When entertaining, Lawrence recommends a mix of different styled drinking vessels, to ensure that each guest knows which glass is his or hers, helping to prevent any accidental—and unhygienic—sharing. Melissa Feldman, ELLE Decor, 8 Dec. 2020 Coroner's officials ruled Houston's death accidental and said heart disease and cocaine were contributing factors. CBS News, 19 Nov. 2020 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'accidental.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of accidental


14th century, in the meaning defined at sense 2


14th century, in the meaning defined at sense 1

History and Etymology for accidental


Middle English, borrowed from Anglo-French accidentel, borrowed from Late Latin accidentālis, from Latin accident-, accidens accident + -ālis -al entry 1


Middle English, borrowed from Medieval Latin accidentālis, noun derivative of Late Latin accidentālis accidental entry 1

Learn More About accidental

Time Traveler for accidental

Time Traveler

The first known use of accidental was in the 14th century

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Dictionary Entries Near accidental



accidental error

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Last Updated

14 May 2022

Cite this Entry

“Accidental.” Dictionary, Merriam-Webster, Accessed 18 May. 2022.

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More Definitions for accidental


ac·​ci·​den·​tal | \ ˌak-sə-ˈden-tᵊl How to pronounce accidental (audio) \

Kids Definition of accidental

1 : happening by chance or unexpectedly an accidental discovery
2 : not happening or done on purpose an accidental shooting

Other Words from accidental

accidentally adverb I broke it accidentally.

More from Merriam-Webster on accidental

Nglish: Translation of accidental for Spanish Speakers

Britannica English: Translation of accidental for Arabic Speakers Encyclopedia article about accidental


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