margin of error

American  

[mahr-jin uhv er-er] / ˈmɑr dʒɪn əv ˈɛr ər /

noun

1. Statistics. 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.

2. Also margin for error 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.

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Etymology

Origin of margin of error

First recorded in 1855–60

Example Sentences

The actual discrepancy, Tinoco said, was 103 votes, a variance of 0.016% that was far below what he said was the state’s preferred 2% margin of error for certifying results.

From Los Angeles Times • Mar. 21, 2026

Source: KFF survey of 1,117 ACA enrollees, Feb. 12- March 2, margin of error: +/- 4 pct. pts.

From The Wall Street Journal • Mar. 19, 2026

Pulling back on spendable income means families have a smaller margin of error if things go wrong, and may compromise the level of financial support parents can offer college-bound or adult children.

From MarketWatch • Mar. 14, 2026

"So while the game is still on for all the English sides, the margin of error is tiny for some of them now."

From BBC • Mar. 11, 2026

‘We saw two capsules empty out before his came down and several after. I timed how long he was up with my watch. There is only a small margin of error possible.’

From "The London Eye Mystery" by Siobhan Dowd