Origin: Latin suffix -al
Accidental has 5 different meanings across 2 categories:
a musical notation that makes a note sharp or flat or natural although that is not part of the key signature
"The composer added an accidental to indicate that the B should be played as a natural, even though the key signature required it to be flat."
A property which is not essential; a nonessential; anything happening accidentally.
"The accidental inclusion of extra sugar made the recipe slightly sweeter than intended."
In plain English: An accidental is an unexpected event that happens by chance rather than on purpose.
"The accidental caused by his clumsy slip destroyed several important documents in the office."
happening by chance or unexpectedly or unintentionally
"with an inadvertent gesture she swept the vase off the table"
"accidental poisoning"
"an accidental shooting"
not of prime or central importance
"nonessential to the integral meanings of poetry"
"the character's motives remain accidental to the plot"
Not essential; incidental, secondary.
"The recipe calls for salt as a main ingredient but lists sugar as an accidental addition to balance the flavor."
In plain English: Something that is accidental happens by mistake instead of on purpose.
"I spilled my coffee by accident, but I was not trying to make a mess."
Usage: Use accidental to describe something that happens by chance rather than on purpose or design. This word applies only when an event occurs without intention, distinguishing it from outcomes caused deliberately.
The word comes from the Middle English form of the Old French term for "pertaining to an accident." It originally meant something that happens by chance rather than by design.