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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.

Synonym Usage

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

Etymology

Origin of accidental

First recorded in 1350–1400; Middle English word from Medieval Latin word accidentālis. See accident, -al 1

Explanation

Anything accidental happens by chance or unintentionally. People don't mean to do accidental things. An accident is something unforeseen that no one wanted to happen, like a car accident or getting hit by lightning. You can describe anything like that as accidental. Bumping into a stranger could be accidental. Forgetting to pay a bill is accidental. This word covers all the things that no one really meant or planned to happen. There are a lot of accidental events in the world, which is one reason insurance exists.

Keep Reading on Vocabulary.com

Vocabulary lists containing accidental

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.

Gangani Publishing tried to market the book online and, in mid 2012, they posted on an online forum called The Accidental Smallholder which is designed to provide support for smallholders and gardeners.

From BBC • Mar. 19, 2026

Accidental artwork sounds like the kind of thing Yoko Ono would be very pleased with.

From Salon • Nov. 25, 2025

Accidental Sanitation-Department Fine: The outcome of artists confusing material maximalism with mastery.

From The Wall Street Journal • Oct. 17, 2025

“I’m just as happy to wear bangles that cost me three dollars as I am to wear valuable pieces,” she wrote in her book, “Iris Apfel: Accidental Icon.”

From Los Angeles Times • Mar. 1, 2024

This paragraph from Accidental Millionaire, one of the many Jobs biographies, gives us a sense of how extraordinary his childhood experiences were.

From "Outliers" by Malcolm Gladwell

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