1. large circular or oval buildings with rows of seats rising around a central open space, used for entertainment or sports
2. outdoor theaters with semicircular seating areas built into hillsides or slopes
3. natural formations resembling theater seating, such as valleys surrounded by rising terrain
Usage: geological

Examples

• The Roman Colosseum is one of the most famous ancient amphitheaters.
• Many universities have outdoor amphitheaters for graduation ceremonies.
• The concert was held in a beautiful hillside amphitheater.
• Students gathered in the campus amphitheater for the poetry reading.
• The natural amphitheater provided excellent acoustics for the performance.
• Modern amphitheaters often feature state-of-the-art sound systems.
• The ancient Greeks built amphitheaters that are still used today.