Definition of: theorem

(thē′ər·əm, thir′əm) noun
1. A proposition demonstrably true or acknowledged as such.
2. Math. a A proposition setting forth something to be proved. b A proposition that has been proved or assumed to be true. c A rule or statement of relations formulated in symbols. [<F théorème <Gk. theōrēma sight, theory <theōreein look at]
—the·o·re·mat·ic (thē′ər·ə·mat′ik), the′o·rem′ic (-ə·rem′ik) adjective