The most common and most likely answer to this crossword clue is the 5 letter word ODEON
I've seen this crossword clue in The Times
O
D
E
O
N
More clues leading to the result ODEON
- Lyric poem about a concert hall
- Where to see films on demand, except occasional Netflix premieres
- A few lines about Greek theatre
- Cinema showing extract from episode one
- Classical theatre Oswald's outside a very long time
- Old academic describing European cinema
- Lyric poem about concert hall
- Work of poet being performed in cinema?
- Show place, extremely old dilapidated one
- Cinema screening Episode 1 in full? On the contrary
Buddy explains!

The straight part
We know that "a concert hall" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case a concert hall = odeon.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does ODEON mean?
ODEON noun- An ancient Greek or Roman building used for performances of music and poetry.
- A theatre or concert hall.