- happening by chance or accident; not planned; unexpected: an accidental meeting.
- nonessential; incidental; subsidiary: accidental benefits.
- Music. relating to or indicating sharps, flats, or naturals.
- a nonessential or subsidiary circumstance, characteristic, or feature.
- Music. a sign placed before a note indicating a chromatic alteration of its pitch.
- occurring by chance, unexpectedly, or unintentionally
- nonessential; incidental
- music denoting sharps, flats, or naturals that are not in the key signature of a piece
- logic (of a property) not essential; contingent
- an incidental, nonessential, or supplementary circumstance, factor, or attribute
- music a symbol denoting a sharp, flat, or natural that is not a part of the key signature
adj.late 14c., “non-essential,” from Old French accidentel or directly from Medieval Latin accidentalis, from Latin accidentem (see accident). Meaning “outside the normal course of nature” is from early 15c.; that of “coming by chance” is from 1570s. n.late 14c., “non-essential quality,” from accidental (adj.). The musical sense is from 1868.