Derrida's concept of différance — the simultaneously spatial (differing) and temporal (deferring) play of differences through which meaning is constituted without ever arriving at full presence — is enacted in Mallarmé's poetry, which Derrida reads as the foundational text of deconstructive poetics; Language poetry's refusal of transparent meaning — the displacement of reference, the foregrounding of signification's instability — enacts the philosophical logic of différance at the level of poetic practice; A poet working with etymologies might illustrate différance by tracing how a word's meaning has been constituted through its differences from other words and deferred across historical time — the word "philosophy" itself carries a chain of differentiation and deferral; Celan's compressed, deferred meanings — where the poem seems to approach a center of meaning that perpetually withdraws — can be read as an enactment of différance in the poetry of testimony; The way rhyme works in poetry — where one sound defers to another, meaning is produced through difference rather than presence — is a concrete illustration of différance as a formal principle: the first rhyme term's meaning is incomplete until the second term arrives, and that second term introduces new differences; Dickinson's dashes — which break and defer the flow of meaning, producing gaps where the reader must supply connections — enact at the typographical level the philosophical logic of différance: meaning is always arriving through a process of deferral and difference