Dictionary.com
Thesaurus.com
Synonyms

truism

American  
[troo-iz-uhm] / ˈtru ɪz əm /

noun

  1. a self-evident, obvious truth.

    Synonyms:
    platitude, cliché

truism British  
/ ˈtruːɪzəm /

noun

  1. an obvious truth; platitude

"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

Commonly Confused

Contrary to what some people believe, the word truism is not a more elegant word for truth. While the word truth can occasionally be used to refer to a “truism,” since truisms are often true, the reverse—the use of truism to mean “truth”—is unwise. Truism stands for a certain kind of truth—a cliché, a platitude, something so self-evident that it is hardly worth mentioning. One can use it to accuse another writer or speaker of saying something so obvious or evident and trite that pointing it out is pointless. To say that a statement is a truism when you intend to compliment it as truthful, factual, even provable, will merely serve to confuse those who know that calling something a truism is not praise, but a criticism or insult. Note, however, that truism is used in a technical sense in mathematics or philosophy for restating something that is already known from its terms or premises. Examples of such truisms include: “Men are not women” and “Since the circumference of a circle equals twice the radius multiplied by π (2π r ), it equals the diameter multiplied by π (π d ).”

Other Word Forms

  • truistic adjective
  • truistical adjective

Etymology

Origin of truism

First recorded in 1700–10; true + -ism

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.

"There's a very commonly accepted truism in pediatric medicine that the face mirrors the brain, because the brain and the face form at the same time," Golding said.

From Science Daily • Mar. 27, 2026

Another market truism is “do not fight the Fed,” but investors should remember that stocks can still push higher even if borrowing costs do not come down much more.

From Barron's • Dec. 10, 2025

The mayor seems not to have heard of the truism that if you tax something you get less of it.

From The Wall Street Journal • Oct. 31, 2025

This is more than just a simple truism.

From BBC • May 16, 2025

The Adams presidency, in fact, might be the classic example of the historical truism that inherited circumstances define the parameters within which presidential leadership takes shape, that history shapes presidents, rather than vice versa.

From "Founding Brothers: The Revolutionary Generation" by Joseph J. Ellis