καταχρηστικῶς.  A technical term in Grammar, applied to the use of a word in a derived or metaphorical sense.  See Aristotle’s description of the various kinds of metaphor, Poet. § xxi. 7–16.  The opposite to καταχρηστικῶς is κυρίως, as used in a parallel passage by Athanasius, Oratio i. contra Arianos, § 21 fin.  “It belongs to the Godhead alone, that the Father is properly (κυρίως) Father, and the Son properly Son.”