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Synonyms

mastermind

American  
[mas-ter-mahynd, mah-ster-] / ˈmæs tərˌmaɪnd, ˈmɑ stər- /

verb (used with object)

  1. to plan and direct (a usually complex project or activity), especially skillfully.

    Two colonels had masterminded the revolt.

noun

  1. a person who originates or is primarily responsible for the execution of a particular idea, project, or the like.

    the masterminds of company policy.
mastermind British  
/ ˈmɑːstəˌmaɪnd /

verb

  1. (tr) to plan and direct (a complex undertaking)

    he masterminded the robbery
"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

noun

  1. a person of great intelligence or executive talent, esp one who directs an undertaking

"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

Etymology

Origin of mastermind

First recorded in 1710–20; master + mind

Explanation

A mastermind is a brilliant thinker with original ideas. You might be a chess mastermind or a criminal mastermind: either way, people will not want to oppose you. Inventors, intellectuals, and famous geniuses call all be called masterminds, from Albert Einstein to theoretical physicist Dr. Shirley Jackson. You could also call people who are successful in their fields — especially if they come up with new ways of doing things — masterminds. Even a brilliant jewel thief might be called a safe-cracking mastermind. As a verb, to mastermind is to act as the leader of some complex plan or scheme.

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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.

The mastermind behind ASML’s unlikeliest hit product is a data analyst named Rick Lenssen—or, as he’s now known to some colleagues, Brick Lenssen.

From The Wall Street Journal • Apr. 20, 2026

“Hannah was the mastermind who figured out four nesting possibilities.”

From Los Angeles Times • Apr. 8, 2026

Cook was the mastermind of the strategy that made China the primary manufacturing base for Apple devices, with the vast majority of iPhones assembled by contractor Foxconn and other suppliers in Chinese factories.

From Barron's • Mar. 29, 2026

Mohsin Naqvi said an Afghan national who is alleged to be the mastermind behind the attack was among those detained.

From BBC • Feb. 7, 2026

In the trial of Vincenzo Perugia, there was no mastermind.

From "The Mona Lisa Vanishes" by Nicholas Day

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.