A tercet is three lines of poetry forming a stanza or complete poem. Haiku is an example of an unrhymed tercet poem. The Chinese poem Quatrain on Heavenly Mountain by Emperor Gaozong (Song Dynasty) Poetry (from the Greek , poiesis, making or creating) is a form of art in which language is used for its aesthetic qualities in addition to, or in lieu of, its ostensible meaning. ... In poetry, a stanza is a unit within a larger poem. ... Haiku )   is a mode of Japanese poetry, the late 19th century revision by Masaoka Shiki of the older hokku ), the opening verse of a linked verse form, haikai no renga. ...

Other types of tercet include an enclosed tercet where the lines rhyme in an a b a pattern and terza rima where the a b a pattern of a verse is continued in the next verse by making the outer lines of the next stanza rhyme with the central line of the preceding stanza as in Dante Alighieri's Divine Comedy. The tercet also forms part of the villanelle, where the initial five stanzas are tercets, followed by a concluding quatrain. Terza rima is a rhyming verse stanza form that was first used by the Italian poet Dante Alighieri. ... Dante in a fresco series of famous men by Andrea del Castagno, ca. ... Dante shown holding a copy of The Divine Comedy, next to the entrance to Hell, the seven terraces of Mount Purgatory and the city of Florence, in Michelinos fresco. ... A villanelle is a poetic form which entered English-language poetry in the late 1800s from the imitation of French models. ... A quatrain is a poem or a stanza within a poem that consists of four lines. ...

A tercet may also be separate halves of the ending sestet in a petrarchan sonnet where the rhyme scheme is abbaabba cdccdc as in Longfellow's "Cross of Snow." It also ends sestinas where the keywords of the lines before are repeated in a highly ordered form. [[]]A Sestet is the name given to the second division of a sonnet, which must consist of an octave, of eight lines, succeeded by a sestet, of six lines. ... The sestina is a highly structured form of poetry, invented by the Provençal troubadour Arnaut Daniel the late 12th century. ...

A tercet is usually made up of three lines and can also be a rhyme pattern of "aba cdc efe ghg etc..".