supervaluation (n.)

A technique used in logic and FORMAL SEMANTICS for dealing with COMPLEX SENTENCES containing CONSTITUENT CLAUSES which are neither true nor false, as in some analyses of PRESUPPOSITION or VAGUENESS. A sentence is assigned the value supertrue if it is true relative to all ways of resolving the truth value of any constituent clauses which lack a TRUTH VALUE, and superfalse if it is false relative to all ways of resolving such truth values.