Plain Song
Cantus planus, the most ancient and simple form of church music, consisting of easy progressions in one of the church modes, suitable for use by priests or a congregation; it is opposed to cantus figuratus, or figurate song, containing more ornate progressions of a later period. When counterpoint was introduced, it was customary to compose parts above or below a portion of ancient plain song, hence, the term plain song is often synonymous with Canto into fermo, or the fixed melody to which counterpoint is added. The term as used in these days includes roughly, ancient chants, inflections, and melodies of the church. Called also plain chant and sometimes plain singing. Also the who enters or one who commences a suit in law against lodges a complaint in a court of law; another; opposed to defendant.