ETYM Latin Calliope, Greek Kallioph, lit, the beautiful-voiced; pref. kalli- (from kalos beautiful) + ops, opos, voice.
A musical instrument consisting of a series of steam whistles played from a keyboard; SYN. steam organ.

(Greek mythology) The Muse of epic poetry.
In Greek mythology, the Muse of epic poetry, and so the most important of all the Muses.