ophicleide [Gr.,=serpent with keys], brass wind musical instrument of relatively wide conical bore, largest of the keyed bugles; invented in 1817 by Jean-Hilaire Asté of Paris. It had from 8 to 11 keys and a full, loud tone; since its intonation was deficient, however, it was soon displaced in the orchestra by the bass tuba. Many composers scored for it before the tuba was available.