Real Dictionary

sestina in American English
an elaborate verse form of six six-line stanzas and a tercet: the end words of the first stanza are repeated in varying combinations in the other five stanzas and the tercet
noun: a poem of six six-line stanzas and a three-line envoy, originally without rhyme, in which each stanza repeats the end words of the lines of the first stanza, but in different order, the envoy using the six words again, three in the middle of the lines and

sestina in British English
noun: an elaborate verse form of Italian origin, normally unrhymed, consisting of six stanzas of six lines each and a concluding tercet. The six final words of the lines in the first stanza are repeated in a different order in each of the remaining five stanzas