adj Common

arbitrary

AH-bih-truh-ree

Arbitrary (adj) means based on personal choice or chance rather than any clear reason, rule, or system. Example: “The rule felt completely arbitrary — nobody could explain why it existed.”

adj

Based on personal choice or chance rather than any clear reason, rule, or system.

"The rule felt completely arbitrary — nobody could explain why it existed."

"They picked a seemingly arbitrary cutoff date for applications."

Used, in mathematics and logic, to mean "any one you like" out of all the possibilities — not random in the everyday sense, but unspecified.

"Let n be an arbitrary positive integer."

How to Use Arbitrary

Learner’s notes

In plain EnglishDecided without a clear reason, or (in maths) simply "any given one".

Common mistake

In everyday use "arbitrary" often carries a negative sense of "unfair" or "unjustified"; in maths and logic it's neutral, just meaning "unspecified".

Common pairings

arbitrary decision arbitrary rule seemingly arbitrary

Word Forms

more arbitrary comparative, arbitraries plural, most arbitrary superlative

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Fill the Gap

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The rule felt completely _____ — nobody could explain why it existed.

Etymology

From Latin arbitrarius, "uncertain, subject to a judge's discretion", from arbiter, "judge".

Origin: Latin

Rhymes for arbitrary

vary Mary nary wary Gary Cary diary ovary weary scary teary deary

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Frequently Asked Questions

What does “arbitrary” mean?

The word “arbitrary” means based on personal choice or chance rather than any clear reason, rule, or system. In plain terms, decided without a clear reason, or (in maths) simply "any given one".

How do you pronounce “arbitrary”?

“Arbitrary” is pronounced AH-bih-truh-ree (/ˈɑɹ.bɪˌtɹɛ(ə).ɹi/ in IPA).

How do you use “arbitrary” in a sentence?

Here is “arbitrary” used in a sentence: “The rule felt completely arbitrary — nobody could explain why it existed.”

What part of speech is “arbitrary”?

“Arbitrary” is an adjective.

Where does the word “arbitrary” come from?

The word “arbitrary” comes from Latin. From Latin arbitrarius, "uncertain, subject to a judge's discretion", from arbiter, "judge".

Is “arbitrary” a common word?

“Arbitrary” is a fairly common word in modern English.

How many meanings does “arbitrary” have?

“Arbitrary” has 2 distinct senses listed in this dictionary. The most common is: based on personal choice or chance rather than any clear reason, rule, or system.

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