The euphonium is a large, conical-bore, baritone-voiced brass instrument that derives its name from the Greek word euphonos, meaning "well-sounding" or "sweet-voiced" (eu means "well" or "good" and phonos means "of sound", hence "of good sound"). The euphonium is a valved instrument; nearly all current models are piston valved, though rotary valved models do exist. The euphonium is a non-transposing instrument known for its distinctive tone color, wide range, variety of character and agility. A person who plays the euphonium is sometimes called a euphoniumist, euphophonist, or a euphonist, while British players often colloquially refer to themselves as euphists, or euphologists. Similarly, the instrument itself is often referred to as eupho or euph.