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known quantity

American  

noun

  1. Mathematics. a quantity whose value is given: in algebra, frequently represented by a letter from the first part of the alphabet, as a, b, or c.

  2. any factor, circumstance, etc., that is already accepted or familiar.

    Her honesty is a known quantity.


Etymology

Origin of known quantity

First recorded in 1975–80

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Mr. Farage is a known quantity after more than a decade in the spotlight following his leadership of the successful referendum campaign to leave the European Union in 2016.

From The Wall Street Journal May 8, 2026

Todd Blanche is a known quantity in Trump World.

From Salon Apr. 22, 2026

As such, Warsh is a known quantity in upper-echelon social, political, and economic circles.

From Barron's Feb. 2, 2026

Now a known quantity, Saints reduced their kicking to Caluori to deal with the breakout star's freakish aerial ability, while the teenager struggled to get the ball in hand to show his running power.

From BBC Oct. 27, 2025

The comparative heating power of fuels is ascertained by burning them in an apparatus, so constructed, that the heat generated shall expend itself in evaporating or raising the temperature of a known quantity of water.

From Peat and its Uses as Fertilizer and Fuel by Johnson, Samuel W. (Samuel William)

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