Trilemma \Tri*lem"ma\, n. [NL., fr. Gr. ? (see {Tri-}) + {?} any thing received, in logic, an assumption. Cf. {Dilemma}.] 1. (Logic) A syllogism with three conditional propositions, the major premises of which are disjunctively affirmed in the minor. See {Dilemma}. [1913 Webster] 2. A state of things in which it is difficult to determine which one of three courses to pursue. [1913 Webster]