Definition and background:
Playing the notes of a chord consecutively ( harp style). A broken chord in which the individual notes are sounded one after the other instead of simultaneously. like a harp; i.e., the notes of the chords are to be played quickly one after another (usually ascending) instead of simultaneously. In music for piano, this is sometimes a solution in playing a wide-ranging chord whose notes cannot be played otherwise. Arpeggios are frequently used as an accompaniment. See also broken chord in this list.chord wherein the tones are struck in sequence, rather than together, and usually sustained
Italian, arpeggiare meaning to play the harp. The notes of a chord played in rapid succession.
For more information on the music term "Arpeggio" check out these other resources:
Wikipedia - Glossary of Musical Terminology
Virginia Tech Multimedia Music Dictionary
ORB -- Medieval Music Glossary