Ballad stanza
In poetry, a ballad stanza is the four-line stanza, known as a quatrain, most often found in the folk ballad. This form consists of alternating four- and three-stress lines. Usually only the second and fourth lines rhyme. Assonance in place of rhyme is common. Samuel Taylor Coleridge adopted the ballad stanza in The Rime of the Ancient Mariner, alternating eight and six syllable lines.
The longer first and third lines are rarely rhymed, although at times poets may use internal rhyme in these lines.
A more modern example:
