Calliope /kə-līˈə-pi or kaˈli-ōp/

1. The Muse of epic poetry (Gr myth)
2. (without cap) a keyboard musical instrument similar to an organ, with a set of whistles operated by steam or compressed air

• orthorhombic
• orthos
• orthoscopic
• orthoses
• orthosilicate
• orthosilicates
• orthosilicic
• orthosis
• orthostatic
• orthostichies
• orthostichous
• orthostichy
• orthotic
• orthotics
• orthotist
• orthotists
• orthotone
• orthotoneses
• orthotonesis
• orthotonic
• orthotopic
• orthotropic
• orthotropies
• orthotropism
• orthotropisms