- a deviation above or below a given statistic encompassing the range within which the true value is most likely to fall, equal to one-half the span of the confidence interval: The poll of likely voters has a margin of error of plus or minus 3.5 percentage points.
- an amount of extra space, time, resources, etc., allowed to account for mistakes, miscalculations, or altered circumstances: The margin of error in the restaurant business is usually razor thin.There’s no margin for error with this new deadline, because you’re handing in final papers the day before grades are due.
