n.1 an event that is without apparent cause, or is unexpected (their early arrival was just an accident).
2 an unfortunate event, esp. one causing physical harm or damage, brought about unintentionally.
3 occurrence of things by chance; the working of fortune (accident accounts for much in life).
4 colloq. an occurrence of involuntary urination or defecation.
5 an irregularity in structure.
Phrases and idioms:
accident-prone (of a person) subject to frequent accidents. by accident unintentionally.
Etymology: ME f. OF f. LL accidens f. L accidere (as AC-, cadere fall)