Perpetuum mobile

In music, perpetuum mobile, moto perpetuo (Italian), mouvement perpétuel (French), movimento perpétuo (Portuguese) movimiento perpetuo (Spanish), is a term used to describe a rapidly executed and persistently maintained figuration, usually of notes of equal length. Over time it has taken on two distinct applications: first, as describing entire musical compositions or passages within them that are characterised by a continuous stream of notes, usually but not always at a rapid tempo; and second, as describing entire compositions, or extended passages within them that are meant to be played in a repetitious fashion, often an indefinite number of times.