The most common and most likely answer to this crossword clue is the 8 letter word GYMNASIA
I've seen this crossword clue in Independent
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More clues leading to the result GYMNASIA
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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 GYMNASIA mean?
GYMNASIA noun- A large room or building for indoor sports.
- A type of secondary school in some European countries which typically prepares students for university.
- A public place or building where Ancient Greek youths took exercise, with running and wrestling grounds, baths, and halls for conversation.