Plagal mode, also known as the plagal cadence, is a musical concept referring to a particular type of harmony and melody. This mode is characterized by a descending, cadential progression that typically falls from the subdominant to the tonic. Many synonyms can be used to describe the Plagal mode, including the "Amen Mode" since its most common use is in Gregorian chants where the word Amen can be found at the end of each hymn. It is also known as the "Lydian-predominant" or the "Dominant-predominant" mode. Other terms like "softened endings," "undulate," "deferential" and "devotional" can also be used to describe the Plagal mode. The Plagal mode brings an inherent sense of calm and resolution, making it a popular mood in religious music.