A coincidence is where two events appear similar or to be related but are not.
- Car A is traveling down the interstate when it is sideswiped by a tractor trailer, flips over, and catches fire.
- Car B, two miles down the same interstate at the same time, suffers an engine overheat because of poor maintenance and catches fire.
Two cars catch fire on the same day at the same time within a short distance of each other. Coincidence? Yes. The events don't share the same cause or have anything to do with one another, other than the close proximity and timing of their occurrence. Close proximity and/or timing are the hallmarks of coincidence.