v. 1 plan, devise, conceive, think up, engineer, design, generate, create, manage, organize, develop, work up or out It was probably Fu Manchu who masterminded this diabolical plot
n. 2 planner, contriver, conceiver, creator, architect, genius, mind, intellect, Colloq brain(s) it would take a mastermind to get even a pass mark on that exam