accidental

The story

1. Late Latin · derived fromaccidēntālis
2. Middle French · derived fromaccidentel
3. Anglo-Norman · derived fromaccidentel
4. Middle English · inherited fromaccidental
5. English todayaccidental

From Middle English accidental, from Anglo-Norman accidentel, Middle French accidentel, accidental, and their source, Late Latin accidēntālis; corresponding to accident + -al.

First known use, by meaning

• from 14th c. Pertaining to accident and not essence; thus, inessential; incidental; secondary.
• from 14th c. Nonessential to something's inherent nature (especially in Aristotelian thought).
• from 16th c. Adjusted by one or two semitones, in temporary departure from the key signature.
• from 16th c. Occurring sometimes, by chance; occasional.
• from 16th c. Happening by chance, or unexpectedly; taking place not according to the usual course of things; by accident, unintentional.