# perpetuum mobile

> English word · Noun · IPA /pəːˌpɛtjʊəm ˈməʊbɪleɪ/

## Definitions
1. A perpetual motion machine.
2. Pieces of music, or parts of pieces, characterised by a continuous steady stream of notes, usually at a rapid tempo.
3. Whole pieces, or large parts of pieces, which are to be played repeatedly, often an indefinite number of times.

## Etymology
From Latin perpetuum (neutral inflection of perpetuus “perpetual”) + Latin mōbile (neutrum of mōbilis “mobile, moving”), used together as a noun, thus literally meaning “perpetual mover”. Although often said to literally mean “perpetual motion”, the latter in Latin is mōtus perpetuus. A perpetuum mobile is a device that exhibits perpetual motion.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/perpetuum-mobile