Happening by chance, or unexpectedly; taking place not according to the usual course of things; by accident, unintentional.
Occurring sometimes, by chance; occasional.
Being a double point with two distinct tangent planes in 4-dimensional projective space.
Adjusted by one or two semitones, in temporary departure from the key signature.
Pertaining to accident and not essence; thus, inessential; incidental; secondary.
Nonessential to something's inherent nature (especially in Aristotelian thought).
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.
A property which is not essential; a nonessential; anything happening accidentally.
A sharp, flat, or natural, occurring not at the commencement of a piece of music as the signature, but before a particular note.
Part of a text that has a mainly structural purpose, such as spelling, punctuation, or capitalization.
Not expected or anticipated; unforeseen.
Not looked for, not searched for.