The crossword solution for the term 'Calliope Cousin' is 'ORGAN', which is a five-letter word. An ORGAN is a type of musical instrument that produces sound by using air to vibrate metal or wooden pipes. It is often used in churches and other places of worship, as well as in classical music. The Calliope is a type of ORGAN that produces a loud, shrill sound, and is often used in carnivals and circuses. A cousin is a relative, so the term 'Calliope Cousin' could refer to someone related to the person who plays the Calliope ORGAN.