echo chamber

That is, in poetry more than in any other verbal genre, readers bring an expectation that not only do all the elements matter down to the comma and the white space at the end of a line and between or within stanzas, but that each of those elements, no matter how widely arrayed, may tug at other elements and condition the whole. The poem is an echo chamber where we listen to the reverberations that otherwise dissolve into the white noise of anxiety.

—Lee Upton, “Poetry, Defined. Briefly.” Swallowing the Sea: On Writing & Ambition Boredom Purity & Secrecy (Tupelo Press, 2012)