outlier

American  

[out-lahy-er] / ˈaʊtˌlaɪ ər /

noun

1. something that lies outside the main body or group that it is a part of, such as a cow far from the rest of the herd, or a distant island belonging to a cluster of islands.

   The small factory was an outlier, and unproductive, so the corporation sold it off to private owners who were able to make it profitable.

2. someone who stands apart from other members of a group, such as by differing behavior, beliefs, or religious practices.

   There are a few scientists who are outliers in their views on climate change.

   Synonyms:

   outsider, heretic, iconoclast, dissenter, dissident, bohemian, eccentric, original, maverick, nonconformist

3. Statistics.

   1. an observation that is well outside of the expected range of values in a study or experiment, and which is often discarded from the data set.

      Experience with a variety of data-reduction problems has led to several strategies for dealing with outliers in data sets.

   2. a person whose abilities, achievements, etc., lie outside the range of statistical probability.

4. Geology. a part of a formation left detached through the removal of surrounding parts by erosion.

5. Obsolete. a person residing outside the place of their business, duty, etc.

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outlier British  

/ ˈaʊtˌlaɪə /

noun

1. an outcrop of rocks that is entirely surrounded by older rocks

2. a person, thing, or part situated away from a main or related body

3. a person who lives away from his place of work, duty, etc

4. statistics a point in a sample widely separated from the main cluster of points in the sample See scatter diagram

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Etymology

Origin of outlier

First recorded in 1600–10; out- + lier

Example Sentences

It must be mentioned they did beat England to win Euro 2020 in the midst of that, but that has proved an outlier.

From BBC • Mar. 25, 2026

One notable outlier is Saudi Arabia, where women outnumber men in the AI-skilled talent pool.

From Barron's • Mar. 22, 2026

To be sure, a rate cut at the meeting next week is an outlier forecast.

From MarketWatch • Mar. 14, 2026

But as Burton’s team writes in their clemency petition to Ivey, Burton’s case is an extreme outlier, “a quintessential case for the exercise of executive clemency.”

From Slate • Mar. 6, 2026

This was a first, even for an outlier like me.

From "Tradition" by Brendan Kiely

Related Words

• aberration
• deviation
• eccentricity
• exception
• oddity