Meaning: not contaminated; clean and pure.

Part of speech: adjective

Example: The unpolluted river was a great spot for fishing.

Category: Nature

Synonyms:

• clean
• pure

Antonyms:

• polluted
• contaminated

Meaning: Never done or known before.

Part of speech: adjective

Example: The pandemic caused unprecedented changes in daily life.

Category: Politics

Synonyms:

• extraordinary
• unmatched

Antonyms:

• common
• usual

Meaning: Not having or showing bias or prejudice.

Part of speech: adjective

Example: She approached the situation with an unprejudiced mind.

Category: Social Issues

Synonyms:

• impartial
• fair

Antonyms:

• biased
• prejudiced

Meaning: Not acting in accordance with moral principles.

Part of speech: adjective

Example: His unprincipled behavior shocked his colleagues.

Category: Business › Ethics

Synonyms:

• immoral
• dishonest

Antonyms:

• principled
• ethical

Meaning: Not able to be pronounced; difficult to say.

Part of speech: adjective

Example: The name was so long it seemed unpronounceable.

Category: Language

Synonyms:

• inarticulate
• indecipherable

Antonyms:

• pronounceable
• articulate

Meaning: Not demonstrated to be true or valid.

Part of speech: adjective

Example: The theory remains unproven.

Category: Science › Research

Synonyms:

• unverified
• untested

Antonyms:

• proven
• verified

Meaning: Not punished for wrongdoing.

Part of speech: adjective

Example: The crime went unpunished.

Category: Law › Criminal Law

Synonyms:

• unaccountable
• unreprimanded

Antonyms:

• punished
• reprimanded

Meaning: Not able to be questioned; certain.

Part of speech: adjective

Example: Her talent is unquestionable.

Category: Arts

Synonyms:

• indisputable
• undeniable

Antonyms:

• questionable
• doubtful

Meaning: Not doubted or challenged.

Part of speech: adjective

Example: His authority was unquestioned.

Category: Politics

Synonyms:

• accepted
• acknowledged

Antonyms:

• questioned
• doubted

Meaning: Not achieved or brought into reality.

Part of speech: adjective

Example: Her dreams remained unrealized.

Category: Personal Development

Synonyms:

• unfulfilled
• unaccomplished

Antonyms:

• realized
• achieved

Meaning: Not able to be recognized; unfamiliar.

Part of speech: adjective

Example: The city was unrecognizable after the renovations.

Category: Arts › Urban Development

Synonyms:

• unfamiliar
• unknown

Antonyms:

• recognizable
• familiar

Meaning: Not documented or officially noted.

Part of speech: adjective

Example: Many unrecorded species exist in the rainforest.

Category: Science › Biology

Synonyms:

• unnoted
• unregistered

Antonyms:

• recorded
• documented

Meaning: The quality of being unreliable; lack of dependability.

Part of speech: noun

Example: Unreliability can lead to lost clients.

Category: Business › Management

Synonyms:

• instability
• inconsistency

Antonyms:

• reliability
• dependability

Meaning: Not representative; not typical of a group.

Part of speech: adjective

Example: The sample was unrepresentative of the population.

Category: Statistics

Synonyms:

• atypical
• unusual

Antonyms:

• representative
• typical

Meaning: Not limited or restricted; complete.

Part of speech: adjective

Example: She gave her unreserved support.

Category: Social Issues

Synonyms:

• wholehearted
• unconditional

Antonyms:

• reserved
• conditional

Meaning: Not reacting or responding; indifferent.

Part of speech: adjective

Example: The patient was unresponsive to treatment.

Category: Medicine › Patient Care

Synonyms:

• indifferent
• unreactive

Antonyms:

• responsive
• reactive

Meaning: Calm and composed; not agitated.

Part of speech: adjective

Example: She remained unruffled during the crisis.

Category: Social Issues

Synonyms:

• calm
• composed

Antonyms:

• agitated
• flustered

Meaning: Not able to be sold; unsellable.

Part of speech: adjective

Example: The product was deemed unsaleable due to defects.

Category: Business

Synonyms:

• unsellable
• unmarketable

Antonyms:

• saleable
• marketable

Meaning: unpleasant or morally offensive

Part of speech: adjective

Example: The politician was involved in some unsavoury scandals.

Category: Politics

Synonyms:

• disreputable
• unpleasant

Antonyms:

• pleasant
• agreeable

Meaning: not based on or consistent with scientific methods

Part of speech: adjective

Example: His claims were dismissed as unscientific.

Category: Science

Synonyms:

• irrational
• unfounded

Antonyms:

• scientific
• empirical

Meaning: having or showing no moral principles

Part of speech: adjective

Example: The unscrupulous businessman took advantage of his clients.

Category: Business

Synonyms:

• unethical
• immoral

Antonyms:

• ethical
• principled

Meaning: to remove someone from a position or office

Part of speech: verb

Example: The election aimed to unseat the incumbent mayor.

Category: Politics

Synonyms:

• oust
• remove

Antonyms:

• seat
• appoint

Meaning: not able to see or perceive

Part of speech: adjective

Example: He walked through the crowd with an unseeing gaze.

Category: Psychology

Synonyms:

• blind
• unaware

Antonyms:

• seeing
• aware

Meaning: not proper or appropriate

Part of speech: adjective

Example: His unseemly behavior at the party shocked everyone.

Category: Social

Synonyms:

• improper
• indecent

Antonyms:

• proper
• decent

Meaning: not influenced by emotional feelings

Part of speech: adjective

Example: He had an unsentimental view of life.

Category: Psychology

Synonyms:

• pragmatic
• rational

Antonyms:

• sentimental
• emotional

Meaning: not able to be shaken or disturbed

Part of speech: adjective

Example: Her faith in the project was unshakable.

Category: Psychology

Synonyms:

• steadfast
• firm

Antonyms:

• shakable
• unstable

Meaning: not disturbed or affected

Part of speech: adjective

Example: He remained unshaken by the criticism.

Category: Psychology

Synonyms:

• calm
• steady

Antonyms:

• shaken
• disturbed

Meaning: not safe or reliable

Part of speech: adjective

Example: The building was declared unsound after the inspection.

Category: Safety

Synonyms:

• unsafe
• flawed

Antonyms:

• sound
• safe

Meaning: not fair or honorable in sports

Part of speech: adjective

Example: His unsporting behavior during the game was criticized.

Category: Sports

Synonyms:

• unfair
• dishonorable

Antonyms:

• sporting
• fair

Meaning: not behaving in a fair or honorable way in sports

Part of speech: adjective

Example: His unsportsmanlike conduct led to a penalty.

Category: Sports

Synonyms:

• unfair
• dishonorable

Antonyms:

• sportsmanlike
• fair

Meaning: not emphasized or highlighted

Part of speech: adjective

Example: In this sentence, the word is unstressed.

Category: Linguistics

Synonyms:

• unemphasized
• neutral

Antonyms:

• stressed
• emphasized

Meaning: not suspected or thought to be true

Part of speech: adjective

Example: The suspect had an unsuspected motive.

Category: Law

Synonyms:

• unforeseen
• unexpected

Antonyms:

• suspected
• expected

Meaning: not able to be maintained at the current rate or level

Part of speech: adjective

Example: The current practices are unsustainable for the environment.

Category: Environment

Synonyms:

• unmaintainable
• impractical

Antonyms:

• sustainable
• viable

Meaning: not showing sympathy or compassion

Part of speech: adjective

Example: His unsympathetic remarks upset her.

Category: Psychology

Synonyms:

• cold
• indifferent

Antonyms:

• sympathetic
• compassionate

Meaning: Too unlikely or extreme to be considered.

Part of speech: adjective

Example: The idea of losing the championship was unthinkable for the team.

Category: Arts

Synonyms:

• inconceivable
• impossible

Antonyms:

• thinkable
• believable

Meaning: Not using thought or consideration.

Part of speech: adjective

Example: His unthinking remarks hurt her feelings.

Category: Psychology

Synonyms:

• thoughtless
• careless

Antonyms:

• thoughtful
• considerate

Meaning: Occurring at an inappropriate time.

Part of speech: adjective

Example: His untimely death shocked everyone.

Category: Health

Synonyms:

• premature
• inopportune

Antonyms:

• timely
• opportune

Meaning: Too great to be counted or measured.

Part of speech: adjective

Example: The war caused untold suffering.

Category: History

Synonyms:

• countless
• innumerable

Antonyms:

• counted
• measured

Meaning: A false statement; a lie.

Part of speech: noun

Example: He was caught telling an untruth.

Category: Philosophy

Synonyms:

• lie
• falsehood

Antonyms:

• truth
• fact

Meaning: Not typical; unusual.

Part of speech: adjective

Example: His behavior was untypical for someone in his position.

Category: Behavior

Synonyms:

• atypical
• unusual

Antonyms:

• typical
• usual