[trai'lemә]
n.
三难困难,三难选择的窘境,[逻]三难推理

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}.

2. A state of things in which it is difficult to determine
which one of three courses to pursue.