arbitrary
Americanadjective
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subject to individual will or judgment without restriction; contingent solely upon one's discretion.
an arbitrary decision.
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decided by a judge or arbiter rather than by a law or statute.
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having unlimited power; uncontrolled or unrestricted by law; despotic; tyrannical.
an arbitrary government.
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based on whim or personal preference, without reason or pattern; random.
This is an unusual encyclopedia, arranged by topics in a more or less arbitrary order.
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Mathematics. undetermined; not assigned a specific value.
an arbitrary constant.
noun
plural
arbitrariesadjective
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founded on or subject to personal whims, prejudices, etc; capricious
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having only relative application or relevance; not absolute
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(of a government, ruler, etc) despotic or dictatorial
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maths not representing any specific value
an arbitrary constant
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law (esp of a penalty or punishment) not laid down by statute; within the court's discretion
Other Word Forms
- arbitrarily adverb
- arbitrariness noun
- nonarbitrary adjective
- unarbitrary adjective
Etymology
Origin of arbitrary
First recorded in 1400–50; late Middle English, from Latin arbitrārius “uncertain” (i.e., depending on an arbiter's decision); arbiter, -ary
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 DOJ has long claimed that the policy was not arbitrary but carefully laid out in a May 2025 email about “Courthouse Arrest Guidance and Case Adjudication.”
From Slate • Mar. 27, 2026
In her ruling, she said the government's designation of Anthropic as a supply chain risk was "likely both contrary to law and arbitrary and capricious."
From Barron's • Mar. 26, 2026
“Bad years for the S&P 500 are due to very specific factors, not just bad luck or arbitrary changes in investor sentiment,” said Nicholas Colas, co-founder of DataTrek, in commentary shared with MarketWatch on Tuesday.
From MarketWatch • Mar. 24, 2026
France previously described Ryan's detention as "arbitrary" and demanded his immediate release.
From BBC • Mar. 16, 2026
We shared other traits as well, alas: He was rebellious and resentful of authority, quick to rage at arbitrary power.
From "Geeks: How Two Lost Boys Rode the Internet Out of Idaho" by Jon Katz
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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.