noun

• (music) The notes of a chord played individually instead of simultaneously, usually moving from lowest to highest.
  "He struck the opening chords of the passage; but this time Irene's voice was silent. Victor stopped in the middle of an arpeggio."

verb

• (transitive) To play (a chord) as an arpeggio; to play (a piece of music) with arpeggios.
  "1819, Abraham Rees (ed.), The Cyclopædia, London: Longman, Hurst, Rees, Orme & Brown, Volume 14, entry “Fingering on Keyed Instruments,” In practising quick passages, the fingers should be lifted up with a spring, and not allowed to hang on the keys, till wanted again, unless in arpeggioing chords, or in passages of expression."
• (intransitive) To produce arpeggios; to produce sounds resembling arpeggios.
  "Herr Schlitz seated himself on the piano chair, pushed it a little back, drew it a little forward to the original place, looked under the piano at the pedals, took out his handkerchief and wiped his face and hands, and after arpeggioing up and down the keyboard, swung into a waltz of Chopin’s […]"
• (ambitransitive, figurative) To move (the hand or fingers) against a surface as if playing arpeggios on a keyboard; to touch different points in succession along a surface.
  "Her hand was still arpeggioing softly on his arm."