known quantity

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.

Word History and Origins

Origin of known quantity¹

First recorded in 1975–80

Example Sentences

Still, with some unknowns in the Chargers’ receiving corps outside of Ladd McConkey and Quentin Johnston, it makes sense that they would want to bolster their passing game with a more known quantity in a player such as Allen.

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He is, in other words, a known quantity.

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As opposed to the much more “easy reader” version, which is bringing the same sensibility to the same music and feeling stuck but giving your fans a known quantity they can eat and consume year in and year out.

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But several former military and Pentagon officials said that Hegseth was not a known quantity in the Washington defence community.

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It is worth stating the obvious too – while Sir Keir and Harris have never met, she is a vastly more known quantity and far more likely to be conventional in her approach to high office than her rival.

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