arpeggio
Concise Oxford English Dictionary © 2008 Oxford University Press:
arpeggio /ɑːˈpɛdʒɪəʊ/
▶noun (pl. arpeggios) Music the notes of a chord played in rapid succession.
– origin Ital., from arpeggiare ‘play the harp’, from arpa ‘harp’.
'arpeggio' also found in these Oxford entries:

