common denominator

American  

noun

1. Mathematics. a number that is a multiple of all the denominators of a set of fractions.

2. a trait, characteristic, belief, or the like common to or shared by all members of a group.

   Dedication to the cause of freedom was the common denominator of the American revolutionaries.

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common denominator British  

noun

1. an integer exactly divisible by each denominator of a group of fractions: 1/ 3 , 1/ 4 , and 1/ 6 have a common denominator of 12

2. a belief, attribute, etc, held in common by members of a class or group

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common denominator Scientific  

1. A quantity into which all the denominators of a set of fractions may be divided without a remainder. For example, the fractions 1/3 and 2/5 have a common denominator of 15.

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common denominator Cultural  

1. A number that will allow fractions with different denominators to be converted into fractions with the same denominator, so that these fractions can be added or subtracted. The fractions can be expressed as whole numbers divided by the common denominator. Thus, 12 is a common denominator for 1/3 and 1/4, since they can be written as 4/12 and 3/12, respectively. (See lowest common denominator.)

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Discover More

Figuratively, a common denominator is a common factor in different events: “The common denominator in these crimes is the use of inside knowledge of computer systems.”

Etymology

Origin of common denominator

First recorded in 1585–95

Example Sentences

If Gellar didn’t have such a spellbinding screen presence, one might think she was the common denominator factor in all of these failed series.

From Salon • Mar. 26, 2026

The common denominator: Even when leagues investigate aggressively, the current system relies on prosecutors to finish the job.

From MarketWatch • Mar. 18, 2026

Each is embarking on a distinct changeover path, but the common denominator of resetting is unmistakable and momentous.

From Barron's • Dec. 18, 2025

That’s “diworsification”—ideas watered down to the lowest common denominator, the least innovative option that offends no one.

From The Wall Street Journal • Nov. 26, 2025

It deflates them, reduces them to the common denominator where they can be dealt with.

From "The Handmaid's Tale" by Margaret Atwood