theorize

verb

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

intransitive verb

: to form a theory : speculate

transitive verb

1
: to form a theory about
2
: to propose as a theory
theorization
ˌthē-ə-rə-ˈzā-shən How to pronounce theorize (audio)
ˌthir-ə-
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.
Slower drivers, urban planners theorize, can encourage economic growth in addition to keeping streets safer. — Fort Worth Star-Telegram, 28 Aug. 2026 This guy theorized that the debate had something to do with the cross-town rivalry between the city’s two high schools. — Martha Ross, Mercury News, 27 Aug. 2026 But doctoral student Jonathan Carcache theorizes that the lousewort is helping its neighbors as much as stealing from them. — ABC News, 25 Aug. 2026 At the Lowell Observatory in Arizona, he was dedicated to finding a ninth planet, which had long been theorized by scientists but never found. — Victoria Edel, PEOPLE, 24 Aug. 2026 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

Rhymes for theorize

See All Rhymes for theorize

Browse Nearby Words

theorization
theorize
theorizer
See all Nearby Words

Cite this Entry

“Theorize.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/theorize. Accessed 1 Sep. 2026.

Copy Citation

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

Thesaurus: All synonyms and antonyms for theorize

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Popular in Grammar & Usage

See More

A Who’s Who Regarding ‘Who’s’ and ‘Whose’

Is it 'nerve-racking' or 'nerve-wracking'?

What's the difference between 'fascism' and 'socialism'?

Why does English have so many silent letters?

7 Pairs of Commonly Confused Words
See More

Popular in Wordplay

See More

Ye Olde Nincompoop: Old-Fashioned Words for 'Stupid'

14 Phobias You Probably Haven't Heard Of

Even More Words That Sound Like Insults But Aren't

Even More Bird Names that Sound Like Insults (and Sometimes Are)

12 Lovely and Unusual Words for the Natural World
See More

Popular

See More

A Who’s Who Regarding ‘Who’s’ and ‘Whose’

Ye Olde Nincompoop: Old-Fashioned Words for 'Stupid'

14 Phobias You Probably Haven't Heard Of
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
The Missing Letter A daily crossword with a twist
skateboard-dog-hat
Wordmaxxing Slang Quiz Give your vocabulary a glow up by getting sendy w...
See All