S: (v) conspire, cabal, complot, conjure, machinate (engage in plotting or enter into a conspiracy, swear together) "They conspired to overthrow the government"
S: (v) plot (plan secretly, usually something illegal) "They plotted the overthrow of the government"
S: (v) plan (make plans for something) "He is planning a trip with his family"
S: (v) think, cogitate, cerebrate (use or exercise the mind or one's power of reason in order to make inferences, decisions, or arrive at a solution or judgments) "I've been thinking all day and getting nowhere"