thereby

adverb

1
: by that : by that means
thereby lost her chance to win
2
: connected with or with reference to that
… thereby hangs a tale …—William Shakespeare

Examples of thereby in a Sentence

He signed the contract, thereby forfeiting his right to the property.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
In 1984 the late mathematician Vaughan Jones introduced a new way to assign polynomials to knots, thereby tangling the two fields together. — Lyndie Chiou, Scientific American, 2 Oct. 2026 Deterioration is exacerbated if water reaches the steel rebar, corroding from inside the concrete mass and thereby weakening the integrity of the wall. — Jeffrey Weiss, Artforum, 1 Oct. 2026 And not just any velociraptor, but the enraged dinosaur that pushed franchise champion Rachel Reilly into a volcano, thereby burning the reality TV icon to a crisp in a sea of lava. — Dalton Ross, Entertainment Weekly, 1 Oct. 2026 Will there be a long delay due to further security scrutiny, thereby slowing down ChatGPT releases? — James Peckham, PC Magazine, 29 Sep. 2026 See All Example Sentences for thereby

Word History

First Known Use

before the 12th century, in the meaning defined at sense 1

Time Traveler
The first known use of thereby was before the 12th century

Cite this Entry

“Thereby.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thereby. Accessed 9 Oct. 2026.

Kids Definition

thereby

adverb
there·​by t͟ha(ə)r-ˈbī How to pronounce thereby (audio)
t͟he(ə)r-;
ˈt͟ha(ə)r-ˌbī, 
ˈt͟he(ə)r-
1
: by that : by that means
thereby lost her chance to win
2
: connected with or with reference to that
thereby hangs a tale
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