(n.) Accident; chance; casualty.

accident accidentality actuarial calculation adventitiousness adventure break casualness casualty chance chance hit contingency contingent destiny fate fluke flukiness fortuitousness fortune freak accident gamble good fortune good luck hap happening happenstance happy chance hazard heedless hap how they fall indeterminacy indeterminateness law of averages long odds long shot lot luck lucky shot moira opportunity principle of indeterminacy probability problematicness random sample risk run of luck serendipity statistical probability the breaks theory of probability uncertainty uncertainty principle whatever comes