noun. A song or melody; especially, an ecclesiastical melody or style of music.

noun. Plain-song in particular.

noun. A musical rendering of a liturgy, as contrasted with mere reading.

noun. A melody or song, particularly ecclesiastical.

noun. The principal voice.

"Consequently, the term cantus is not to be limited to songs which are really sung and set to melodies, but can be applied as well to every religious lyrical poem which can be sung and set to music."

cantus ambrosianus  cantus ecclesiasticus  cantus figuratus  cantus firmus  cantus gregorianus  

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