Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “arbitrary”


adjective    /ˈɑr·bɪˌtrer·i/
based on a desire or idea or chance rather than reason: Her outfit was an arbitrary choice but was just perfect. arbitrarily    /ˌɑr·bəˈtreər·ə·li/ adverb We didn’t think much about it, just arbitrarily decided to go to Italy. arbitrariness    /ˌɑr·bəˈtreər·i·nəs/ noun [U] disapproving The arbitrariness of human nature infuriates me.
(Definition of arbitrary adjective from the Cambridge Academic Content Dictionary © Cambridge University Press)
Focus on the pronunciation of arbitrary

Definitions of “arbitrary” in other dictionaries

Word of the Day


showing a wish to help or bring advantages to others, even if it results in disadvantage for yourself

Word of the Day


Read our blog about how the English language behaves.

Learn More

New Words

Find words and meanings that have just started to be used in English, and let us know what you think of them.

Learn More