The article investigates how the problem of (linguistic) reference is treated in Gilbert of Poitiers’ Commentaries on Boethius’ Opuscula sacra. In this text the terms supponere, suppositus,-a,-um, and suppositio mainly concern the act of a speaker (or of the author of a written text) that consists of referring—by choosing a name as subject term in a proposition—to one or more subsistent things as what the speech act (or the written text) is about. Supposition is for Gilbert an action performed by a speaker, not a property of terms, and his ‘contextual approach’ has a pragmatic touch: “we do not predicate in order to supposit as much as we supposit in order to predicate”. Language is considered by Gilbert as a system for communication between human beings, key notions are the ‘sense in the author’s mind’ (sensus mentis eius qui loquitur) and the ‘interpreter’s understanding’ (intelligentia lectoris). The phenomenon of ‘disciplinal’ discourse (“man is a species of individuals”) is treated by means of these hermeneutic notions and not by means of a special kind of supposition.