heresy

American  

[her-uh-see] / ˈhɛr ə si /

noun

plural

heresies

1. opinion or doctrine at variance with the orthodox or accepted doctrine, especially of a church or religious system.

2. the maintaining of such an opinion or doctrine.

3. Roman Catholic Church. the willful and persistent rejection of any article of faith by a baptized member of the church.

4. any belief or theory that is strongly at variance with established beliefs, customs, etc.

   Synonyms:

   dissension, iconoclasm, dissent

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heresy British  

/ ˈhɛrəsɪ /

noun

1. 1. an opinion or doctrine contrary to the orthodox tenets of a religious body or church

   2. the act of maintaining such an opinion or doctrine

2. any opinion or belief that is or is thought to be contrary to official or established theory

3. belief in or adherence to unorthodox opinion

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heresy Cultural  

1. A belief or teaching considered unacceptable by a religious group. (See heretic.)

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Other Word Forms

• superheresy noun

Etymology

Origin of heresy

First recorded in 1175–1225; Middle English heresie, from Old French eresie, from Latin haeresis “school of thought, sect,” from Greek haíresis, literally, “act of choosing,” derivative of haireîn “to choose”

Explanation

A heresy is a belief that doesn't agree with the official tenets of a particular religion; heresy is the maintaining of such contrary beliefs. Heresy can be used figuratively: to disagree with the school committee's decisions is considered pure heresy by the faculty. You'll often come across this word in a religious context — the Latin root haeresis, "school of thought or sect," was used by Christian writers to mean "unorthodox sect or belief." This comes from the Greek hairesis, "a taking or choosing," from hairein, "to choose." A person who chooses to believe in heresies is called a heretic.

Example Sentences

When Ferrari revealed the Purosangue three years ago, many in the red brigade derided the design and, more generally, the very idea of a Ferrari sport-utility vehicle, scorning it as a sort of heresy.

From The Wall Street Journal • Apr. 18, 2026

"This is eminently reasonable but was treated for many years as heresy," he added.

From BBC • Jul. 15, 2025

His brother confirmed in an interview with the city’s local station WGN-TV that he is a White Sox fan, refuting early heresy claiming he roots for the Cubs, aka Satan’s Stickballers.

From Salon • May 10, 2025

I realize this is heresy, but I think it’s important to acknowledge the irreducible strangeness of the drama.

From Los Angeles Times • Nov. 4, 2024

Anaxagoras, Protagoras, and of course Socrates were hauled up on charges of heresy and impiety.

From "Circumference" by Nicholas Nicastro

Related Words

• blasphemy
• fallacy