• WordNet 3.6
    • n sestet a rhythmic group of six lines of verse
    • n sestet a musical composition written for six performers
    • n sestet a set of six similar things considered as a unit
    • n sestet six performers or singers who perform together
    • n sestet the cardinal number that is the sum of five and one
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Webster's Revised Unabridged Dictionary
    • Sestet (Mus) A piece of music composed for six voices or six instruments; a sextet; -- called also sestuor.
    • Sestet (Poet) The last six lines of a sonnet.
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Century Dictionary and Cyclopedia
    • n sestet In music, same as sextet.
    • n sestet The two concluding stanzas of a sonnet, consisting of three lines each; the last six lines of a sonnet.
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Chambers's Twentieth Century Dictionary
    • n Sestet ses′tet the last six lines of a sonnet forming two stanzas of three lines each:
    • n Sestet ses′tet (mus.) same as Sextet.
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Webster's Revised Unabridged Dictionary
It. sestetto, fr. sesto, sixth, L. sextus, fr. sex, six
Chambers's Twentieth Century Dictionary
It. sestettosesto—L. sextus, sixth.


In literature:

The octet was finished and the first two lines of the sestet.
"Orpheus in Mayfair and Other Stories and Sketches" by Maurice Baring
The sestet continues: Nevertheless, do not let the memory of me become a burden, especially if you ever learn what was in my living thoughts.
"The Principles of English Versification" by Paull Franklin Baum
In the sestet usually the first line rhymes with the fourth, the second with the fifth and the third with the sixth.
"Journeys Through Bookland, Vol. 10" by Charles Herbert Sylvester
I confess, though, that I did not know that Petrarch had made so frequent use of the 2-rhyme sestet.
"The Letters of Ambrose Bierce" by Ambrose Bierce
One of these must be in the octave and the other in the sestet.
"The Circus, and Other Essays and Fugitive Pieces" by Joyce Kilmer
The more important chamber compositions include a sestet for piano and strings, a trio, and a sonata for violincello and piano.
"A Short History of English Music" by Ernest Ford