Organum
That's a "round".
Sisters with voices
voices in a trio
Crazy as it sounds- and NO relation to the Broadway musical with a related name- Calcutta, it was largely an instrumental with some choral non-singing ( if you know what I mean) voices. Song was somewhat similar to ( The Third Man) but different.
Oratorio is defined as a large-scale musical work for orchestra and voices, typically a narrative on a religious theme, performed without the use of costumes, scenery, or action. Well-known examples include Bach's Christmas Oratorio, Handel's Messiah, and Haydn's The Creation.
parts
round
A round is a type of musical composition where multiple voices sing the same melody but start at different times, creating harmonies. The most famous example is "Frère Jacques" (Brother John) which has the same melody and words but starts at different times.
A fugue features a single theme, the "subject," that is introduced and then imitated in different voices, creating a complex polyphonic texture. In contrast, a canon involves the repetition of a melody in different voices, with each voice entering at a set time interval and playing the same melody, creating a layered effect. Ultimately, a fugue is more rhythmically and harmonically complex than a canon.
it is the melody or succsesion of tones for one of the voices or instruments
direct psalmody
Simply it's a choir. So 16 voices is a choir of 16.
Arrangement, in music terms means to alter the original composition so as to: make it usable for another instrument; make the the rhythm different; make it usable for voices instead of instruments, etc. Any way you alter a composition to make it sound differently without altering the melody is an arrangement.
That's a "round".
polyphony
song
The official defetinion is:contrapuntal composition in two or more voices, built on a subject (theme) that is introduced at the beginning in imitation and recurs frequently in the course of the composition.click in the related links box below for the wikipedia article on the fugue.