A person who conspires; one who plots secretly with others to do something wrong.
From Latin conspirare (to plot together), present participle conspirans. This is a formal or legal term meaning 'one who conspires.'
You'll mostly see 'conspirant' in legal documents and formal writing instead of 'conspirator'—it's the Latinate version of the same concept, like how 'defendant' and 'accused' mean similar things but come from different traditions.
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