The Simple English Wikipedia has an article on: Euphonium Pronunciation IPA (key): /juːˈfəʊnɪəm/ Audio (UK)(file) Noun Singular euphonium Plural euphoniums (countable) (music) A euphonium is a musical instrument that plays notes that are between tenor and bass, such as a baritone. The euphonium looks similar to the tuba.Wikiwand - on Seamless Wikipedia browsing. On steroids.Remove ads