material adequacy the property that belongs to a formal definition of a concept when that definition characterizes or ‘captures’ the extension (or material) of the concept. Intuitively, a formal definition of a concept is materially adequate if and only if it is neither too broad nor too narrow. Tarski advanced the state of philosophical semantics by discovering the criterion of material adequacy of truth definitions contained in his convention T. Material adequacy contrasts with analytic adequacy, which belongs to definitions that provide a faithful analysis. Defining an integer to be even if and only if it is the product of two consecutive integers would be materially adequate but not analytically adequate, whereas defining an integer to be even if and only if it is a multiple of 2 would be both materially and analytically adequate. See also CONVENTION T, DEFINITION , FORMAL SEMANTICS , TARSKI , TRUT. J. Cor.