thief

American  

[theef] / θif /

noun

• thieves
  plural

1. a person who steals, especially secretly or without open force; one guilty of theft or larceny.

   Synonyms:

   highwayman, pickpocket, burglar

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thief British  

/ θiːf /

noun

1. a person who steals something from another

2. criminal law a person who commits theft

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Usage

What does thief mean? A thief is a person who steals, especially in secret and without using force or violence. The plural of thief is thieves. The related noun theft refers to the act or an instance of stealing. In general, intentionally taking something that doesn’t belong to you makes you a thief. The word most commonly refers to a person who steals money or physical property, but a thief can steal other things, such as ideas, information, or intellectual property. The word thief typically refers to a person who steals without anyone noticing, at least not when the theft is taking place. In contrast, a person who steals by using force, violence, or threats of force or violence would more likely be called a robber. Still, the word thief is used generally to refer to someone who steals. In this way, a robber is a kind of thief. Most instances of theft are crimes, but a person might still be called a thief if they’ve committed a theft that won’t get them arrested. You might call your sibling a thief when they steal a cookie from your plate, for example. Example: I don’t care that he only stole a few things—he stole them, and that makes him a thief.

Synonym Usage

Thief, robber refer to one who steals. A thief takes the goods or property of another by stealth without the latter's knowledge: like a thief in the night. A robber trespasses upon the house, property, or person of another, and makes away with things of value, even at the cost of violence: A robber held up two women on the street.

Other Word Forms

Derived Forms

• thievishness
  noun
• underthief
  noun
• thievish
  adjective
• thievishly
  adverb

Inflected Forms

Nouns

• thieves
  plural

Etymology

Origin of thief

First recorded before 900; Middle English; Old English thēof; cognate with Dutch dief, German Dieb, Old Norse thjōfr, Gothic thiufs

Explanation

A thief is someone who steals something. A thief can be anything from a cyberspace criminal mastermind who steals credit card information around the world, to the petty thief who picks people's pockets on the subway. Some famous thieves (notice the -v- in the plural) include outlaws of the Old West, like Butch Cassidy and Jesse James, and those notorious bank robbers of the 1930s with the memorable names — "Baby Face" Nelson, "Pretty Boy" Floyd, Bonnie and Clyde, Ma Barker, "Machine Gun" Kelly, to name a few. They were so bold (and so brutal) that their activities became a major impetus for the beefing up of the FBI, under J. Edgar Hoover.

Example Sentences

See Examples For:

thief thieves

Installation at a checkout counter takes seconds, often while a thief blocks a clerk’s view with an item such as a 12-pack of paper towels.

From The Wall Street Journal ● Sep. 20, 2026

"They seem to be more organised, out here you have to drive here, you can't be an opportunist thief."

From BBC ● Sep. 16, 2026

“It would have been more honorable to have been an anonymous thief in the night,” Savery said at Monday’s hearing.

From Los Angeles Times ● Aug. 31, 2026

For three glorious seasons between 1983 and 1985, ‘80s kids also had the “Dungeons & Dragons” animated series with its two girl heroes: an acrobat and a thief with an invisibility cloak.

From Salon ● Jun. 24, 2026

This is why I’m here—to find and catch that little thief.

From "Kwame Crashes the Underworld" by Craig Kofi Farmer

In Paramount, even enhanced lighting and cameras weren’t enough to keep thieves away from the “Battlefield Cross and Soldier” art piece outside the city’s civic center.

From Los Angeles Times ● Sep. 22, 2026

But, police say, thieves who arrived at the church under the cover of darkness last month likely saw the artwork as representing something more worldly: quick cash.

From Los Angeles Times ● Sep. 22, 2026

A shop owner has described how she locks her door during opening hours and customers have to ring the bell to get in after her store was targeted by thieves last year.

From BBC ● Sep. 16, 2026

Before dawn on Sept. 8, thieves in southern France broke into what was Impressionist painter Pierre-Auguste Renoir’s last home, now a museum, and escaped with two of his paintings.

From The Wall Street Journal ● Sep. 15, 2026

It was then that the rats were driven to become scavengers and thieves, living on the fringes of a world run by men.

From "Mrs. Frisby and the Rats of NIMH" by Robert C. O'Brien

Related Words

• bandit
• burglar
• criminal
• crook
• mugger
• pickpocket
• pirate
• robber
• sniper
• swindler