Definition
An arbitrary choice is one that reasons cannot explain — from the Latin arbiter, 'judge': what is arbitrary is decided by someone's discretion rather than by any rule the rest of us could check. A border drawn as a straight line through living communities is arbitrary; rules that change weekly are arbitrary; the choice between identical options is arbitrary by necessity. The word carries a quiet accusation: where the arbitrary begins, justification has ended.
Examples
- The colonial border was an arbitrary line that ignored the people living along it.
- Employees complained that the new rules felt arbitrary, changing from week to week.
- When two candidates' merits coincide exactly, any choice between them is arbitrary.
Collocations
an arbitrary decision·seemingly arbitrary·arbitrary rules·an arbitrary line·arbitrary arrest
Synonyms
random·capricious·whimsical·unjustified·discretionary
Antonyms
reasoned·principled·coherent
Word family
arbitrarily (adverb)·arbitrariness (noun)
In TOEFL & IELTS
A TOEFL linguistics classic: passages on language note that 'the relationship between a word and its meaning is arbitrary' — recognize the claim, it gets tested. Science texts speak of arbitrary units and constants; politics passages of arbitrary arrest and arbitrary power. Pronunciation trap: US keeps four syllables with stress up front (/ˈɑːrbətreri/), UK compresses (/ˈɑːbɪtrəri/).