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Synonyms

arbitrary

American  
[ahr-bi-trer-ee] / ˈɑr bɪˌtrɛr i /

adjective

  1. subject to individual will or judgment without restriction; contingent solely upon one's discretion.

    an arbitrary decision.

  2. decided by a judge or arbiter rather than by a law or statute.

  3. having unlimited power; uncontrolled or unrestricted by law; despotic; tyrannical.

    an arbitrary government.

  4. 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.

  5. Mathematics. undetermined; not assigned a specific value.

    an arbitrary constant.


noun

arbitraries plural
  1. Printing. arbitraries, (in Britain) peculiar.

arbitrary British  
/ ˈɑːbɪtrərɪ /

adjective

  1. founded on or subject to personal whims, prejudices, etc; capricious

  2. having only relative application or relevance; not absolute

  3. (of a government, ruler, etc) despotic or dictatorial

  4. maths not representing any specific value

    an arbitrary constant

  5. law (esp of a penalty or punishment) not laid down by statute; within the court's discretion

"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

Other Word Forms

Derived Forms

Inflected Forms

Nouns

Etymology

Origin of arbitrary

First recorded in 1400–50; late Middle English, from Latin arbitrārius “uncertain” (i.e., depending on an arbiter's decision); see origin at arbiter, -ary

Explanation

Something that's arbitrary seems like it's chosen at random instead of following a consistent rule. Team members would dislike their coach using a totally arbitrary method to pick starting players. Even though arbitrary comes from a word meaning "judge" (arbiter), that doesn't mean judges are always fair. Calling a decision-maker arbitrary is usually a negative thing, suggesting the person is making rules based on whim rather than justice. A coach who selects starting players arbitrarily isn't strictly applying a rule; he could just be picking names out of a hat.

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Vocabulary lists containing arbitrary

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.

See Examples For:

My goal is to retire — or at least significantly cut back — by age 60 or 62, with a somewhat arbitrary target of $5 million in retirement savings.

From MarketWatch Jul. 21, 2026

"We could have picked some more arbitrary target," Stoudenmire says.

From Science Daily Jul. 20, 2026

Even after 1964, when Leonid Brezhnev halted reforms, persecuted dissidents and presided over what came to be regarded as “the era of stagnation,” the arbitrary arrests of millions did not resume.

From The Wall Street Journal Jul. 10, 2026

He called his arrest an "arbitrary, capricious prosecution".

From BBC Jun. 21, 2026

“Ted sent me home!”—as if this were some arbitrary injustice.

From "Nickel and Dimed: On (Not) Getting By in America" by Barbara Ehrenreich

Some contained codes, devised by Anson Stager, general manager of U.S. military telegraphs, that inserted decoy words or arbitraries into messages that were unscrambled with cipher charts.

From Los Angeles Times Aug. 19, 2016

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