arbitrary

arbitrary — adjective

1. chosen or arranged without a clear rule, good reason, or careful method, so it m

1.adjectiveC2
Definition

chosen or arranged without a clear rule, good reason, or careful method, so it may feel random.

Example

The ticket system felt arbitrary, and nobody knew why row seven cost more.

linking verb: feel arbitrary

An arbitrary deadline moved the school project two days earlier.

before noun: arbitrary deadline

Common collocations
  • arbitrary decision
  • arbitrary deadline
  • arbitrary limit
  • arbitrary number
  • arbitrary starting point
Synonyms
  • random

    stresses lack of pattern, and does not always suggest a human decision

  • baseless

    focuses on a lack of evidence, especially for claims or beliefs

  • capricious

    is stronger and suggests sudden choices driven by mood or whim

  • haphazard

    stresses disorder or lack of method in the way something is done

Antonyms
  • reasoned

    shows that thought and judgment support the choice

  • systematic

    stresses an ordered method or plan

  • justified

    focuses on having a good reason that can be explained

Grammar Patterns

an arbitrary decision

an arbitrary limit

seem arbitrary

choose something arbitrarily

Usage Note

Usually describes decisions, limits, dates, rankings, or categories created without a clear system. Unlike adjective/2, it does not by itself mean someone is misusing power, though the result may still seem unfair.

Common Mistakes

An arbitrary man stopped me on the street.
A random man stopped me on the street.
arbitrary usually describes choices, numbers, or rules, not an unknown person.
The storm damaged houses in an arbitrary way.
The storm damaged houses at random.
arbitrary often suggests a human choice or system with no clear basis.

2. showing that a person or authority acts only by personal will and ignores other

2.adjectiveC2
Definition

showing that a person or authority acts only by personal will and ignores other people's rights, views, or fair treatment.

Example

Villagers feared the governor's arbitrary orders after the protest.

common with authority nouns

An arbitrary boss cut Yael's pay without hearing her side.

arbitrary + person in power

Common collocations
  • arbitrary power
  • arbitrary rule
  • arbitrary order
  • arbitrary arrest
  • arbitrary authority
Synonyms
  • authoritarian

    stresses demanding obedience and controlling people from the top

  • high-handed

    suggests rude, overconfident use of power in everyday situations

  • despotic

    is stronger and is often used for harsh political rule

  • autocratic

    focuses on power concentrated in one ruler or decision-maker

Antonyms
  • fair

    means people are treated justly and by the same standard

  • lawful

    focuses on acting within legal limits

  • restrained

    suggests power is limited or carefully controlled

Grammar Patterns

arbitrary power

arbitrary rule

arbitrary arrest

an arbitrary ruler

Usage Note

Most often used for rulers, officials, police, bosses, laws, or arrests. Distinguish from adjective/1: here the focus is abuse of power, not simply a choice with no clear reason.

Common Mistakes

Our math teacher is arbitrary because homework is checked every day.
Our math teacher is strict because homework is checked every day.
arbitrary means using power unfairly by personal will, not simply enforcing rules firmly.

Word family

  • arbitrarily
    adverbC2
  • arbitrariness
    nounC2
  • arbiter
    nounC2

Synonym discussion

Sense: adjective/1

For this sense, arbitrary is best when a person, rule, or system makes a choice with no clear reason or method. Random is broader: it means without pattern, and it does not always suggest a human decision. Capricious is stronger and points to sudden changes driven by mood or whim. Baseless is different again, because it usually describes statements, fears, or accusations with no evidence behind them. So a random computer error is not usually arbitrary, but an arbitrary score cut-off is. A capricious manager changes plans from mood; a baseless rumor spreads without facts.

arbitrary ↗random ↗capriciousbaseless

Common collocations

Adverbs

  • completely arbitrary
  • highly arbitrary

Phrases

  • seem arbitrary
  • appear arbitrary

Etymology

LatinFrenchEnglish

Arbitrary came into English through French from Latin arbitrarius, a word linked to arbiter, meaning a judge or someone who gives a decision. From that idea of depending on a person's judgment, the word later developed the modern senses of lacking a clear basis and using personal power as one wishes.