Ophicleide
Ophicleide , noun
[French ophicléide, from Greek 'o`fis a serpent + {not transcribed}, gen. {not transcribed}, a key. So named because it was in effect the serpent, an old musical instrument, with keys added.]
(Music) A large brass wind instrument, formerly used in the orchestra and in military bands, having a loud tone, deep pitch, and a compass of three octaves; -- now generally supplanted by bass and contrabass tubas. It developed from the older wooden instrument called the serpent. — Moore (Encyc. of Music)