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Synonyms

accidental

American  
[ak-si-den-tl] / ˌæk sɪˈdɛn tl /

adjective

  1. happening by chance or accident; not planned; unexpected.

    an accidental meeting.

    Synonyms:
    unintentional
    Antonyms:
    contrived, planned
  2. nonessential; incidental; subsidiary.

    accidental benefits.

  3. Music. relating to or indicating sharps, flats, or naturals.


noun

  1. a nonessential or subsidiary circumstance, characteristic, or feature.

  2. Music. a sign placed before a note indicating a chromatic alteration of its pitch.

accidental British  
/ ˌæksɪˈdɛntəl /

adjective

  1. occurring by chance, unexpectedly, or unintentionally

  2. nonessential; incidental

  3. music denoting sharps, flats, or naturals that are not in the key signature of a piece

  4. logic (of a property) not essential; contingent

"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

noun

  1. an incidental, nonessential, or supplementary circumstance, factor, or attribute

  2. music a symbol denoting a sharp, flat, or natural that is not a part of the key signature

"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

Usage

What does accidental mean? Accidental describes something that happens by chance or without planning, as in The hero has an accidental meeting with the villain early in the movie that sets the hero on his course. Accidental can also sometimes refer to something that comes about by chance. Example: We had to sign a contract saying we are aware of the possibility of accidental injury.

Related Words

Accidental, casual, fortuitous all describe something outside the usual course of events. Accidental implies occurring unexpectedly or by chance: an accidental blow. Casual describes a passing event of slight importance: a casual reference. Fortuitous is applied to events occurring without known cause, often of a fortunate or favorable nature: a fortuitous shower of meteors. It often also implies good luck or good fortune: a fortuitous choice leading to rapid advancement.

Other Word Forms

  • accidentality noun
  • accidentally adverb
  • accidentalness noun
  • accidently adverb
  • nonaccidental adjective
  • nonaccidentalness noun
  • preaccidental adjective
  • pseudoaccidental adjective
  • quasi-accidental adjective
  • unaccidental adjective

Etymology

Origin of accidental

First recorded in 1350–1400; Middle English word from Medieval Latin word accidentālis. See accident, -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.

Dowd emphasized that all rattlesnake bites reported in Ventura County this year have been the result of accidental encounters.

From Los Angeles Times • Apr. 7, 2026

"When I saw the footage, it was immediately clear that this was not accidental," Auersperg says.

From Science Daily • Mar. 26, 2026

After Iran’s accidental downing of Ukrainian Airlines PS752 in 2020, families of those who died have been pressing the International Civil Aviation Organization to set standards restricting flights in conflict zones.

From The Wall Street Journal • Mar. 22, 2026

Police said they were investigating whether the hit was deliberate or accidental.

From BBC • Mar. 22, 2026

The grandfather laughed at his own accidental joke, but Peter didn’t.

From "Pax" by Sara Pennypacker