IPA: //oʊˈdiːən//
KK: /oʊˈdiːən/
A type of building designed for performances, such as music and poetry, often used in ancient Greece and Rome, and also refers to modern theaters.
We went to the odeon to watch a live concert last night.
Odeon comes from the Greek word "odeion" (meaning a building for musical performances), which is derived from "ode" (meaning song or ode). The term originally referred to a theater or hall where music and poetry were performed.
Think of a place where 'songs' ('ode') are performed, which helps you remember that an 'odeon' is a venue for musical performances.