coincidence
     n 1: an event that might have been arranged although it was
          really accidental [syn: {happenstance}]
     2: the quality of occupying the same position or area in space;
        "he waited for the coincidence of the target and the cross
        hairs"
     3: the temporal property of two things happening at the same
        time; "the interval determining the coincidence gate is
        adjustable" [syn: {concurrence}, {conjunction}, {co-occurrence}]
Source: WordNet® 2.0