moto perpetuo
Concise Oxford English Dictionary © 2008 Oxford University Press:
moto perpetuo /ˌməʊtəʊ pəˈpɛtjʊəʊ/
▶noun (pl. moto perpetui) a piece of fast-moving instrumental music consisting mainly of notes of equal length.
– origin Ital., lit. ‘perpetual motion’.
'moto perpetuo' also found in these Oxford entries:

