In the essay "Différance" Derrida indicates that différance gestures at a number of heterogeneous features that govern the production of textual meaning. The first (relating to deferral) is the notion that words and signs can never fully summon forth what they mean, but can only be defined through appeal to additional words, from which they differ. Thus, meaning is forever "deferred" or postponed through an endless chain of signifiers. The second (relating to difference, sometimes referred to as espacement or "spacing") concerns the force that differentiates elements from one another and, in so doing, engenders binary oppositions and hierarchies that underpin meaning itself.