[ ahr-bi-trer-ee ]
See synonyms for: arbitraryarbitrarilyarbitrariness on

  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.

  1. having unlimited power; uncontrolled or unrestricted by law; despotic; tyrannical: an arbitrary government.

  2. 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.

  3. Mathematics. undetermined; not assigned a specific value: an arbitrary constant.

noun,plural ar·bi·trar·ies.
  1. arbitraries, Printing. (in Britain) peculiar (def. 9).

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

Other words from arbitrary

  • ar·bi·trar·i·ly [ahr-bi-trair-uh-lee] /ˌɑr bɪˈtrɛər ə li/ adverb
  • ar·bi·trar·i·ness, noun
  • non·ar·bi·trar·y, adjective
  • un·ar·bi·trar·y, adjective

Words Nearby arbitrary Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use arbitrary in a sentence

British Dictionary definitions for arbitrary


/ (ˈɑːbɪtrərɪ) /

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

  2. having only relative application or relevance; not absolute

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

  2. maths not representing any specific value: an arbitrary constant

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

Origin of arbitrary

C15: from Latin arbitrārius arranged through arbitration, uncertain

Derived forms of arbitrary

  • arbitrarily, adverb
  • arbitrariness, noun

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