Dictionary.com
Thesaurus.com
Synonyms

criminal

American  
[krim-uh-nl] / ˈkrɪm ə nl /

adjective

  1. of the nature of or involving crime.

    Synonyms:
    unlawful, felonious
    Antonyms:
    lawful
  2. guilty of crime.

    Antonyms:
    innocent
  3. Law. of or relating to crime or its punishment.

    a criminal proceeding.

  4. senseless; foolish.

    It's criminal to waste so much good food.

  5. exorbitant; grossly overpriced.

    They charge absolutely criminal prices.


noun

criminals plural
  1. a person guilty or convicted of a crime.

    Synonyms:
    gangster, hoodlum, crook, felon, culprit, transgressor, evildoer, malefactor
criminal British  
/ ˈkrɪmɪnəl /

noun

  1. a person charged with and convicted of crime

  2. a person who commits crimes for a living

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

adjective

  1. of, involving, or guilty of crime

  2. (prenominal) of or relating to crime or its punishment

    criminal court

    criminal lawyer

  3. informal senseless or deplorable

    a criminal waste of money

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

What is a basic definition of criminal? A criminal is a person who commits crime. Criminal is also used to describe something involved in committing crime or related to crime. Criminal has a few other senses as an adjective. A criminal is a person who breaks the law and engages in illegal activity.

  • Real-life examples: Shoplifters, kidnappers, bank robbers, and pirates are all criminals.
  • Used in a sentence: The judged sentenced the two wanted criminals to prison for stealing a car.
As an adjective, criminal describes something involved in or related to committing a crime.
  • Real-life examples: Stealing a car, robbing someone’s house, and printing fake money to use as real money are all criminal acts. They are all against the law, and a person will be arrested if caught doing any of these acts. Police might say a person is accused of criminal activity if they believe the person was doing something illegal.
  • Used in a sentence: The gangster Al Capone was in charge of a criminal organization.
Criminal can also be used to describe something that is related to crime without actually engaging in it.
  • Real-life examples: In the United States, criminal law is a collection of laws that state what the government or society says is a crime and will result in punishment by the state if someone is proved to have broken the law. A criminal lawyer is a lawyer who specializes in criminal law.
  • Used in a sentence: When Jimmy was arrested for breaking into his neighbor’s house, he called a criminal lawyer to help him.

Synonym Usage

See illegal.

Other Word Forms

Derived Forms

Inflected Forms

Nouns

Etymology

Origin of criminal

First recorded in 1350–1400; Middle English, from Anglo-French, from Late Latin crīminālis, from Latin crīmin- (stem of crīmen “accusation, blame, charge”; see crime) + -ālis -al 1

Explanation

A criminal is someone who breaks the law. If you're a murderer, thief, or tax cheat, you're a criminal. When you think of criminals, your first thought might be of someone awful like a murderer. But this word is a lot broader — Anyone who breaks the law is technically a criminal, even if the crime is just not paying a speeding ticket. You can also talk about criminal activities: things that are illegal. Lots of TV shows are about police officers and lawyers trying to catch criminals who are engaged in all kinds of exciting criminal activity.

Keep Reading on Vocabulary.com

Vocabulary lists containing criminal

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

While not involved in the Saunders investigation, the Criminal Cases Review Commission, external looks at miscarriages of justice.

From BBC • Jun. 26, 2026

It says the government must get an order authorizing electronic surveillance through the Foreign Intelligence Surveillance Court under Title 1 or “a warrant issued pursuant to the Federal Rules of Criminal Procedure by a court.”

From The Wall Street Journal • Jun. 8, 2026

But the law does provide exemptions for religious reasons as potential lawful defences under Section 139 of the Criminal Justice Act 1988.

From BBC • Jun. 5, 2026

Criminal court records do not show recent charges against Perry.

From Los Angeles Times • May 30, 2026

One was a representative of the Utah Association of Criminal Defense Lawyers.

From "A Deadly Wandering: A Mystery, a Landmark Investigation, and the Astonishing Science of Attention in the Digital Age" by Matt Richtel

Vocabulary.com logo
by dictionary.com

Look it up. Learn it forever.

Remember "criminal" for good with VocabTrainer. Expand your vocabulary effortlessly with personalized learning tools that adapt to your goals.

Take me to Vocabulary.com