Trojan horse


Definition of Trojan horse

1 : someone or something intended to defeat or subvert from within usually by deceptive means
2 : a seemingly useful computer program that contains concealed instructions which when activated perform an illicit or malicious action (such as destroying data files) also : the concealed instructions of such a program — compare virus sense 3

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Did You Know?

After besieging the walls of Troy for ten years, the Greeks built a huge, hollow wooden horse, secretly filled it with armed warriors, and presented it to the Trojans as a gift for the goddess Athena, and the Trojans took the horse inside the city's walls. That night, the armed Greeks swarmed out and captured and burned the city. A Trojan horse is thus anything that looks innocent but, once accepted, has power to harm or destroy—for example, a computer program that seems helpful but ends up corrupting or demolishing the computer's software.

Examples of Trojan horse in a Sentence

They may be using the other corporation as a Trojan horse.

First Known Use of Trojan horse

1837, in the meaning defined at sense 1

History and Etymology for Trojan horse

from the large hollow wooden horse filled with Greek soldiers and introduced within the walls of Troy by a stratagem

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Time Traveler for Trojan horse

Time Traveler

The first known use of Trojan horse was in 1837

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Cite this Entry

“Trojan horse.” Dictionary, Merriam-Webster, Accessed 7 May. 2021.

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More Definitions for Trojan horse

Trojan horse


English Language Learners Definition of Trojan horse

: someone or something that is used to hide what is true or real in order to trick or harm an enemy
computers : a seemingly useful computer program that is actually designed to harm your computer (such as by destroying data files) if you use it

More from Merriam-Webster on Trojan horse

Thesaurus: All synonyms and antonyms for Trojan horse

Nglish: Translation of Trojan horse for Spanish Speakers

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