ENGLISH
REFERENCE

arbitrary

adj.
C1 Advanced Oxford US //ˈɑɹbəˌtɹɛɹi// UK //ˈɑːbɪtɹəɹi// ar·bi·trary Academic

adj. based on a random choice or personal feeling, rather than a clear reason or system. When a decision is arbitrary, it often feels unfair because there are no clear rules behind it.

adj. determined by chance, whim, or impulse rather than by necessity, reason, or principle. Frequently used to describe decisions or rules that appear to lack a logical foundation or objective standard.


SIMPLE

The teacher's grading system seems completely arbitrary.

CONTEXTUAL

Management set an arbitrary deadline of Friday afternoon, even though the project requires at least another week of testing.

COMPLEX

Critics argued that the border was an arbitrary line drawn by colonial powers, ignoring the historical and cultural realities of the indigenous populations living in the region.

Antonyms
Origin

Etymology tree Latin arbiter Proto-Indo-European *-yósder. Proto-Italic *-āsios Latin -ārius Latin arbitrāriusder. Middle English arbitrarie English arbitrary From Middle English arbitrarie, Latin arbitrārius (“arbitrary, uncertain”), from arbiter (“witness, on-looker, listener, judge, overseer”).

Usage

Functions both attributively and predicatively; frequently collocates with nouns like 'decision', 'rule', 'choice', or 'deadline'.

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