A repeated line, refrain, or recurring element in poetry that suggests endless continuation, eternal recurrence, or perpetual repetition beyond the poem's temporal boundaries. The unceasing echo creates hypnotic, obsessive, or timeless effects through repetition that seems capable of continuing infinitely. Examples include Poe's "Nevermore" in "The Raven," Blake's prophetic refrains, or liturgical responses suggesting eternal cycles. This technique evokes themes of eternity, obsession, inevitability, or the perpetual nature of certain truths, with the echo imagery suggesting both repetition and resonance that fades yet never entirely ceases.

Creates sense of eternal repetition or haunting recurrence. Related to refrain techniques suggesting endless continuation. Common in poems exploring memory, obsession, or eternal themes. The echo imagery suggests both repetition and fading, creating complex temporal effects.