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noun, con·spir·a·cy \kən-ˈspir-ə-sē\

Simple Definition of conspiracy

  • : a secret plan made by two or more people to do something that is harmful or illegal

  • : the act of secretly planning to do something that is harmful or illegal

Source: Merriam-Webster's Learner's Dictionary

Full Definition of conspiracy

plural conspiracies

  1. 1 :  the act of conspiring together

  2. 2 a :  an agreement among conspirators b :  a group of conspirators

Examples of conspiracy in a sentence

  1. The CIA uncovered a conspiracy against the government.

  2. They were accused of conspiracy to commit murder.

Origin of conspiracy

Middle English conspiracie, from Latin conspirare

First Known Use: 14th century

Synonym Discussion of conspiracy

plot, intrigue, machination, conspiracy, cabal mean a plan secretly devised to accomplish an evil or treacherous end. plot implies careful foresight in planning a complex scheme <an assassination plot>. intrigue suggests secret underhanded maneuvering in an atmosphere of duplicity <backstairs intrigue>. machination implies a contriving of annoyances, injuries, or evils by indirect means <the machinations of a party boss>. conspiracy implies a secret agreement among several people usually involving treason or great treachery <a conspiracy to fix prices>. cabal typically applies to political intrigue involving persons of some eminence <a cabal among powerful senators>.

CONSPIRACY Defined for Kids


noun con·spir·a·cy \kən-ˈspir-ə-sē\

Definition of conspiracy for Students

plural conspiracies

  1. 1 :  a secret agreement to do something harmful or unlawful

  2. 2 :  the act of plotting with others to do something harmful or unlawful

  3. 3 :  a group of conspirators

Law Dictionary


noun con·spir·a·cy \kən-ˈspir-ə-sē\

Legal Definition of conspiracy

plural conspiracies

  1. 1 :  an agreement between two or more people to commit an act prohibited by law or to commit a lawful act by means prohibited by law; also :  the crime or tort of participating in a conspiracy — compare substantive crime Editor's note: Some states require an overt act in addition to the agreement to constitute conspiracy. chain conspiracy :  a conspiracy in which the conspirators act separately and successively (as in distributing narcotics) civil conspiracy :  a conspiracy that is not prosecuted as a crime but that forms the grounds for a lawsuit criminal conspiracy :  a conspiracy prosecuted as a crime

  2. 2 :  a group of conspirators

Origin of conspiracy

Latin conspiratio, from conspirare to conspire — see conspire

Seen and Heard

What made you want to look up conspiracy? Please tell us where you read or heard it (including the quote, if possible).


a timid, meek, or unassertive person

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