# accidental

/ˌæksəˈdɛnəɫ/ (US) · /ˌæksɪdˈɛntəl/ (UK)

Source: https://englishreference.com/word/accidental
Updated: 2026-06-20

## Senses

### 1. happening by chance

adjective · CEFR B1

happening by chance or by mistake, rather than being planned.

For teachers: occurring by chance, unexpectedly, or without deliberate intent.

- The police believe the fire was accidental and started in the kitchen.
- The discovery of the ancient coins was entirely accidental, occurring while the construction crew was digging a trench for new water pipes.

### 2. music symbol

noun · CEFR C1 · Technical

a symbol like a sharp or flat that changes a note for a short time.

For teachers: a sign placed before a note which alters its pitch by a semitone, independent of the key signature.

- The pianist missed the accidental in the third bar and played a wrong note.
- The composer used frequent accidentals to create a sense of tonal instability throughout the second movement.

Usage: The noun refers to the symbol itself (the sharp, flat, or natural sign).

### 3. non-essential property

noun · CEFR C2 · Academic · Formal

a quality or feature of something that is not necessary for it to be what it is.

For teachers: a property or attribute that is not part of the essential nature of a thing.

- The color of the car is an accidental; it doesn't change the fact that it is a car.
- In Aristotelian logic, an accidental is a quality that can be changed without the subject losing its fundamental identity.

## Examples

- The composer added an accidental to make the melody sound more mysterious.
- While the piece is written in G major, the frequent use of accidentals creates a chromatic texture that challenges the performer.
- In modern atonal compositions, every note may require an accidental to clarify the intended pitch, as traditional key signatures no longer provide a functional harmonic framework for the performer.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.