Definition

1. Noun:
   • A deceptive strategy or device: A "Trojan horse" is something that appears harmless, useful, or desirable but is used to conceal a hidden, harmful intent or force. This meaning originates from the ancient Greek story.
   • A type of malicious software (malware): In computing, a "Trojan horse" (often shortened to "Trojan") is a program that misleads users about its true purpose, often appearing as legitimate software but performing harmful actions once installed.

Usage

• The term is used to describe a deceptive trick or trap. In computing, it specifically refers to a major category of malware. It is often used with the indefinite article ("a Trojan horse") or as a proper noun when referring to the historical artifact ("the Trojan Horse").

Examples

• Noun (Deceptive Strategy):

  • The new tax law was a Trojan horse, hiding severe cuts to public services.
  • The ancient Greeks used the Trojan Horse to secretly enter the city of Troy.

• Noun (Malware):

  • Never open email attachments from unknown senders; they might contain a Trojan horse.
  • His computer was infected by a Trojan that stole his banking passwords.

Advanced Usage

• "To be a Trojan horse for something": To serve as a deceptive means of introducing or enabling something else.
  • The trade agreement was seen as a Trojan horse for deregulating the industry.

Variants and Related Words

• Trojan (n): A common shortened form, especially in computing contexts (e.g., "a Trojan virus").
• Trojan horse attack (n phr): The specific act of deploying or falling victim to a Trojan horse, especially in cybersecurity.
• Trojan War (n phr): The legendary war from which the original story of the Trojan Horse comes.

Synonyms

• Deception: The act of deceiving.
• Ruse: A trick or stratagem intended to deceive.
• Malware: Malicious software (this is a broader category that includes Trojans).
• Fifth column: A group within a country that works to support its enemies (similar to the subversive group meaning).

Related Phrases

• Beware of Greeks bearing gifts: An idiom derived from the same story, meaning to be suspicious of seemingly generous offers from rivals or enemies.

Noun

1. a large hollow wooden figure of a horse (filled with Greek soldiers) left by the Greeks outside Troy during the Trojan War
2. a program that appears desirable but actually contains something harmful
   • the contents of a trojan can be a virus or a worm
   • when he downloaded the free game it turned out to be a trojan horse
3. a subversive group that supports the enemy and engages in espionage or sabotage; an enemy in your midst