New American Oxford Dictionary
cantus
can tus |ˈkantəs ˈkæntəs | ▶noun the highest voice in polyphonic choral music. ORIGIN late 16th cent.: from Latin.
cantus firmus
can tus fir mus |ˈfərməs ˌkæntəs ˈfərməs | ▶noun ( pl. cantus firmi |ˈfərˌmī, -mē | ) Music an existing melody used as the basis for a polyphonic composition. ORIGIN mid 19th cent.: from Latin, literally ‘firm song. ’
Oxford Dictionary
cantus
cantus |ˈkantəs | ▶noun the highest voice in polyphonic choral music. ORIGIN late 16th cent.: from Latin.
cantus firmus
cantus firmus |ˌkantəs ˈfəːməs | ▶noun ( pl. cantus firmi |ˌkantuːs ˈfəːmʌɪ | ) Music a melody used as the basis for a polyphonic composition. ORIGIN mid 19th cent.: from Latin, literally ‘firm song ’.
Duden Dictionary
Cantus
Can tus Substantiv, maskulin Musik , der |C a ntus |der Cantus; Genitiv: des Cantus, Plural: die Cantus |[ˈkantuːs ]|lateinisch cantus Gesang, Melodie; melodietragende Oberstimme bei mehrstimmigen Gesängen
Cantus firmus
Can tus fir mus Substantiv, maskulin Musik , der |C a ntus f i rmus |der Cantus firmus; des Cantus firmus, die Cantus |[ˈkantuːs ] |firmi zu lateinisch firmus = fest (stehend )Hauptmelodie eines mehrstimmigen Chor- oder Instrumentalsatzes