Noun
A triplet.
A triplet; a group of three lines.
Source: Webster's dictionaryA tercet also ends sestinas where the keywords of the lines before are repeated in a highly ordered form. Source: Internet
Henderson translated every hokku and haiku into a rhymed tercet (a-b-a), whereas the Japanese originals never used rhyme. Source: Internet
There are two refrains and two repeating rhymes, with the first and third line of the first tercet repeated alternately until the last stanza, which includes both repeated lines. Source: Internet