Conspiracy, n.; pl. Conspiracies.
Etymology: [See Conspiration.]
1. A combination of men for an evil purpose; as agreement, between two or more persons, to commit a crime in concert, as treason; a plot. When shapen was all his conspiracy From point to point. Chaucer. They made a conspiracy against [Amaziah]. 2 Kings xiv. 19. I had forgot that foul conspiracy Of the beast Caliban and his confederates. Shak.
2. A concurence or general tendency, as of circumstances, to one event, as if by agreement. A conspiracy in all heavenly and earthly things. Sir P. Sidney.
3. (Law)
An agreement, manifesting itself in words or deeds, by which two or more persons confederate to do an unlawful act, or to use unlawful to do an act which is lawful; confederacy.
1 more senses
Syn. -- Combination; plot; cabal.
Shades of meaning
Fernald has no entry of its own for conspiracy; he lists it under cabal.
Where he writes about it:
A conspiracy is a combination of persons for an evil purpose, or the act of so combining. — from cabal
Conspiracy is a distinct crime under common, and generally under statutory, law. — from cabal
A faction is more extensive than a conspiracy, less formal in organization, less definite in plan. — from cabal
Cabal commonly denotes a conspiracy of leaders. — from cabal