n. 25B6; noun
an accident at work : MISHAP, misadventure, unfortunate incident, mischance, misfortune, disaster, tragedy, catastrophe, calamity; technical casualty.
an accident on the motorway : CRASH, collision, smash, bump, car crash, road traffic accident, RTA; derailment; N. Amer. wreck; informal smash-up, pile-up; Brit. informal prang, shunt.
it is no accident that there is a similarity between them : CHANCE, mere chance, coincidence, twist of fate, freak, hazard; fluke, bit of luck, serendipity; fate, fortuity, fortune, providence, happenstance.