Coliseum-Colosseum | Commonly Confused Words

Coliseum

A large, usually open-air building used for sports events and entertainment.

This word has no antonyms

An ancient large public entertainment structure, famous example is in Rome

This word has no antonyms

Coliseum typically refers to a general large theater or stadium.
Colosseum is specifically the famous ancient amphitheater in Rome.
Remember, the Colosseum with two s for the structure in Rome, which was colossal in size.
Use Coliseum for modern-day equivalents or when talking about large venues that are not the Roman Colosseum.
The two words are often used interchangeably, but historically, they refer to different types of structures.