A piece of music played before a mass; a musical introduction of any sort.
The entrance to a hollow organ or canal; often specifically the entrance to the vagina.
A form of monophonic chant in unison using the Gregorian scale, sung in various Christian churches.
A plain unvarnished statement, without exaggeration.
A cantus firmus or theme chosen for contrapuntal treatment; so called because often an actual fragment of plain-song.
The simple notes of an air, without ornament or variation.