Akademik

accidental
1. adjective
a) Happening by chance, or unexpectedly; taking place not according to the usual course of things; casual; fortuitous

an accidental visit

b) Nonessential; not necessary belonging; incidental

are accidental to a play

Syn: casual, fortuitous, contingent, occasional, adventitious, incidental
2. noun
a) A property which is not essential; a nonessential; anything happening accidentally.
b) Those fortuitous effects produced by luminous rays falling on certain objects so that some parts stand forth in abnormal brightness and other parts are cast into a deep shadow.

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