Etymology

Noun

1. Literally, a befalling; an event that takes place without one's foresight or expectation; an undesigned, sudden, and unexpected event; often, an undesigned and unforeseen occurrence of an afflictive or unfortunate character

   to die by an accident

   • Shakespeare, Othello, I-iii:

     Of moving accidents by flood and field.

   • Trench:

     Thou cam'st not to thy place by accident: It is the very place God meant for thee.

2. A property attached to a word, but not essential to it, as gender, number, case.
3. An unplanned event that results in injury (including death) or occupational illness to person(s) and/or damage to property, exclusive of injury and/or damage caused by action of an enemy or hostile force.
4. A point or mark which may be retained or omitted in a coat of arms
5. A quality or attribute in distinction from the substance, as sweetness, softness.
   • 1902, William James, The Varieties of Religious Experience, Folio Society 2008, p. 171:

     If they went through their growth-crisis in other faiths and other countries, although the essence of the change would be the same [...], its accidents would be different.

6. Any accidental property, fact, or relation; an accidental or nonessential

   Beauty is an accident.

   • J. P. Mahaffy:

     This accident, as I call it, of Athens being situated some miles from the sea.

7. Unusual appearance or effect - Geoffrey Chaucer
8. casus; such unforeseen, extraordinary, extraneous interference as is out of the range of ordinary calculation.
9. An unintended collision or event that causes damage or death.

   There was a huge accident on I5 involving 15 automobiles.

   My insurance is expenive now, mostly because of those two accidents.