whereby

American  

[wair-bahy, hwair-] / wɛərˈbaɪ, ʰwɛər- /

conjunction

1. by what or by which; under the terms of which.

2. Obsolete. by what? how?

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whereby British  

/ wɛəˈbaɪ /

pronoun

1. by or because of which

   the means whereby he took his life

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adverb

1. archaic how? by what means?

   whereby does he recognize me?

Etymology

Origin of whereby

First recorded in 1150–1200, whereby is from the Middle English word wherby. See where, by

Example Sentences

More specifically, the asset limit, whereby beneficiaries can keep only $2,000 in savings, has been frozen since 1989.

From MarketWatch • Mar. 10, 2026

Recently, the Lazard team has been applying a “life cycle score” in its valuation analysis for companies, whereby its quant models value younger companies with more room to grow differently than older, more mature companies.

From Barron's • Mar. 4, 2026

"We all know the analogy whereby forests are the green lungs of the Earth," says Barthel.

From Science Daily • Feb. 24, 2026

Governing body the FIA has proposed a compromise whereby the ratio is measured both at ambient temperature and 130C.

From BBC • Feb. 20, 2026

The immorality of the bantustan policy, whereby 70 percent of the people would be apportioned only 13 percent of the land, was obvious.

From "Long Walk to Freedom" by Nelson Mandela