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theorize

verb

the·​o·​rize ˈthē-ə-ˌrīz How to pronounce theorize (audio)
ˈthir-ˌīz
theorized; theorizing

transitive verb

1
: to form a theory about
2
: to propose as a theory
theorization noun
theorizer noun

Examples of theorize in a Sentence

Many scientists have theorized about the possibility of life on other planets.
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.
Dark matter was theorized in 1933 by astronomer Fritz Zwicky, who found that the visible galaxies of the Coma Cluster lacked the necessary gravitational influence to prevent this cluster from flying apart. Robert Lea, Space.com, 25 Nov. 2025 Since dark matter was conceptualized nearly 100 years ago by Swiss astronomer Fritz Zwicky, the invisible substance theorized to hold galaxies together that is supposedly all around us has largely remained a mystery. Hannah Millington, MSNBC Newsweek, 25 Nov. 2025 Maybe, as comedian Tessa Belle theorized on StraightioLab, Charli XCX really is the new Judd Apatow. Jason P. Frank, Vulture, 20 Nov. 2025 Supports Bone Health One of onions' most powerful compounds is theorized to give a boost to bone health. Melissa Porrey Lpc, Verywell Health, 17 Nov. 2025 See All Example Sentences for theorize

Word History

First Known Use

1644, in the meaning defined at transitive sense 1

Time Traveler
The first known use of theorize was in 1644

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Cite this Entry

“Theorize.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/theorize. Accessed 2 Dec. 2025.

Kids Definition

theorize

verb
the·​o·​rize ˈthē-ə-ˌrīz How to pronounce theorize (audio)
theorized; theorizing
: to form a theory : speculate
theorizer noun

More from Merriam-Webster on theorize

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