ternary form

noun
1.
a musical form in three sections, with the third usually an exact repetition of the first.
Origin
1895-1900
British Dictionary definitions for ternary form

ternary form

noun
1.
a musical structure consisting of two contrasting sections followed by a repetition of the first; the form aba Also called song form
Encyclopedia Article for ternary form

in music, a form consisting of three sections, the third section normally either a literal or a varied repeat of the first. The symmetrical construction of this scheme (aba) provides one of the familiar shapes in Western music; ternary form can be found in music from the Middle Ages (as in the common arrangement antiphon-verse-antiphon in Gregorian chant) to the present day.

Learn more about ternary form with a free trial on Britannica.com