Alcaics are lines or stanzas written in the alcaic meter, a classical Greek and Latin pattern associated with the poet Alcaeus. In English, the term usually means a four-line stanza that follows that classical model, with a distinctive mix of longer and shorter lines. Poets have used alcaics for formal, elevated subjects because the pattern creates a stately, measured movement.
Example
Deep in the dusk the old stone bells begin
Slowly to sound; and the cold fields listen
Under the weight of evening, while the dark hills
Hold their last light.