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Synonyms

theorize

American  
[thee-uh-rahyz, theer-ahyz] / ˈθi əˌraɪz, ˈθɪər aɪz /
especially British, theorise

verb (used without object)

theorized, theorizing
  1. to form a theory or theories.


verb (used with object)

theorized, theorizing
  1. to form a theory or theories about.

theorize British  
/ ˈθɪəˌraɪz /

verb

  1. (intr) to produce or use theories; speculate

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • overtheorization noun
  • overtheorize verb (used without object)
  • theorization noun
  • theorizer noun

Etymology

Origin of theorize

From the Medieval Latin word theōrizāre, dating back to 1630–40. See theory, -ize

Explanation

When you theorize, you come up with an explanation for how something happens, based on ideas that can be tested. You may theorize that your dog is afraid of loud noises after you see her cower under the bed during fireworks and thunderstorms. When someone theorizes, they're not just making a wild guess. They're forming a theory, or a testable explanation that they can confirm through experimentation. After a scientist theorizes and the theory sticks around and is tested again and again in a rigorous way, it becomes an "established theory," like the theory of gravity or plate tectonics theory. The Greek root theorein means "to consider, speculate, or look at."

Keep Reading on Vocabulary.com

Vocabulary lists containing theorize

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Reappropriation works, the researchers theorize, because it signals confidence and humor on the part of the brand, especially when the insult seems mild or unjustified.

From The Wall Street Journal • Feb. 27, 2026

She can imagine, she can theorize, she can try to do justice.

From Los Angeles Times • Dec. 8, 2025

When faced with a particularly puzzling case and not much evidence to go on, Sherlock Holmes once said, “It is a capital mistake to theorize before one has data.”

From Barron's • Nov. 13, 2025

Barry helps the hosts break down the behavior of the markets right now, examine the historical context of record breaking highs, and theorize why the price of the US dollar is still falling.

From Slate • Jul. 5, 2025

One could theorize forever about what makes the perfect parent.

From "Freakonomics: A Rogue Economist Explores the Hidden Side of Everything" by Steven D. Levitt