correlation

American  

[kawr-uh-ley-shuhn, kor-] / ˌkɔr əˈleɪ ʃən, ˌkɒr- /

especially British, corelation

noun

1. mutual relation of two or more things, parts, etc..

   Studies find a positive correlation between severity of illness and nutritional status of the patients.

   Synonyms:

   interconnection, interrelationship, interdependence, equivalence, parallelism, correspondence, similarity

2. the act of correlating or state of being correlated.

3. Statistics. the degree to which two or more attributes or measurements on the same group of elements show a tendency to vary together.

4. Physiology. the interdependence or reciprocal relations of organs or functions.

5. Geology. the demonstrable equivalence, in age or lithology, of two or more stratigraphic units, as formations or members of such.

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correlation British  

/ ˌkɒrɪˈleɪʃən /

noun

1. a mutual or reciprocal relationship between two or more things

2. the act or process of correlating or the state of being correlated

3. statistics the extent of correspondence between the ordering of two variables. Correlation is positive or direct when two variables move in the same direction and negative or inverse when they move in opposite directions

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Pop Culture

—Pearson correlation coefficient: a value between -1 and +1 that represents the relationship between two variables.

Other Word Forms

• correlational adjective
• intercorrelation noun
• miscorrelation noun
• noncorrelation noun

Etymology

Origin of correlation

First recorded in 1555–65; from Medieval Latin: correlātiōn- (stem of correlātiō ); cor-, relation

Explanation

Correlation is something that scientists are often trying to show––is there a correlation between smoking and poor health or between napping and productivity? How about daily flossing and good grades? Correlation derives from the Latin cor- 'together' and -relatio 'relation'––the word is all about things that go together. But beware: just because a study shows a correlation between two variables, it doesn't mean one necessarily causes the other. There is a significant correlation between going to high school and being a teenager, but that doesn't mean that going to high school causes you to be a teenager.

Example Sentences

When I point out this apparent correlation to Panella, he tells me he sees it all the time.

From Salon • Apr. 12, 2026

However, the researchers note that the findings show a correlation, not cause and effect, and that factors like motivation or self-discipline may also influence outcomes.

From Science Daily • Mar. 30, 2026

There isn’t a direct correlation between SpaceX news and Tesla stock yet, but the two companies are getting closer.

From Barron's • Mar. 27, 2026

Studies find a measurable negative correlation between heavy AI use and critical-thinking ability, mediated by what cognitive scientists call off-loading—the brain simply stops doing work it knows a machine will do.

From The Wall Street Journal • Mar. 27, 2026

These considerations, along with the just mentioned correlation between regional population size and societal complexity, have led to a protracted chicken-or-egg debate about the causal relations between food production, population variables, and societal complexity.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond

Related Words

• interaction
• interrelationship
• parallel