Occam's razor

American  

noun

1. the maxim that assumptions introduced to explain a thing must not be multiplied beyond necessity.

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Occam's razor British  

noun

1. a variant spelling of Ockham's razor

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Occam's razor Scientific  

/ ŏk′əmz /

1. A rule in science and philosophy stating that entities should not be multiplied needlessly. This rule is interpreted to mean that the simplest of two or more competing theories is preferable and that an explanation for unknown phenomena should first be attempted in terms of what is already known. Occam's razor is named after the deviser of the rule, English philosopher and theologian William of Ockham (1285?–1349?).

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Etymology

Origin of Occam's razor

First recorded in 1900–05; after William of Occam

Example Sentences

While Endres acknowledges the idea as logically possible, he notes that it runs counter to Occam's razor, the principle that favors simpler explanations.

From Science Daily • Oct. 26, 2025

Asked what he would have done different four years ago, Baffert offered an Occam’s razor kind of answer.

From Los Angeles Times • Apr. 30, 2025

For several interested observers, the swift strokes that produced two long, angled consonants in “Luka” also sharpened Occam’s razor.

From New York Times • Oct. 29, 2021

As for UFOs, Bellows demurred, invoking Occam’s razor: The simplest explanation is the best one.

From Slate • Oct. 18, 2021

And Occam’s razor is not a razor that men shave with but a Law, and it says Entia non sunt multiplicanda praeter necessitatem.

From "The Curious Incident of the Dog in the Night-Time" by Mark Haddon