Unison

Technology / Home Audio / Unison: In music, unison is used to describe an identity of pitch. When two or more tones are sounding at the same frequency or pitch, they are said to be in unison with one another.
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Chant

Entertainment / Music / Chant: Singing in unison, texts in a free rhythm. Similar to the rhythm of speech. MORE

Chorus

Entertainment / Literature / Chorus: (1) A group of singers who stand alongside or off stage from the principal performers in a dramatic or musical performance. (2) The song or refrain that this group of singers sings. In ancient Greece, MORE

Homophony

Entertainment / Music / Homophony: Music written to be sung or played in unison. MORE

Gregorian Chant

Entertainment / Music / Gregorian Chant: Monophonic melody with a freely flowing, unmeasured vocal line: liturgical chant of the Roman Catholic Church. Also plainchant or plainsong. MORE