noun
Etymology
Origin of theorist
Explanation
Someone who considers given facts and comes up with a possible explanation is called a theorist. Theorists observe various phenomena and use reasoning to come up with practical ideas that must be proven. Theorists come up with abstract ideas and then spend their lives trying to prove them. Perhaps the most famous theorist was Albert Einstein, whose theory of relativity is arguably the most famous ever presented. Still, an idea can always be disputed until proven, and theorists are often scoffed at. Einstein himself once said, "No one but a theorist believes his theory; everyone puts faith in a laboratory result but the experimenter himself."
Vocabulary lists containing theorist
Selection Vocabulary 3, Unit 1
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Florida's B.E.S.T. Common Suffixes: -ist
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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.
I’m not in radio, nor am I a famous politician–slash–conspiracy theorist regularly doing interviews with the press.
From Slate • Apr. 18, 2026
From there the thread was picked up by the conspiracy theorist Alex Jones, who has a vast audience on the platform.
From Salon • Apr. 15, 2026
It’s the classic mindset of the conspiracy theorist: The absence of proof of the conspiracy is simply proof of how deep the conspiracy goes!
From MarketWatch • Apr. 3, 2026
One of the earliest readings I encountered was by the theorist David Halperin, who defined “queer” as “whatever is at odds with the normal, the legitimate, the dominant.”
From The Wall Street Journal • Apr. 2, 2026
Cicero was the great eminence of the Roman age—a lawyer, a politician, and so not only Rome’s greatest theorist of rhetoric but its greatest practitioner.
From "Words Like Loaded Pistols" by Sam Leith
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.