The most common and most likely answer to this crossword clue is the 9 letter word GRUELLING
I've seen this crossword clue in Financial Times
G
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More clues leading to the result GRUELLING
- Demanding porridge and fish
- Tough coming together around sport
- Sport in setting hard to endure
- Thin soup with fish is hard to get through
- Extremely difficult game in set against Heather
- Very tough food largely put by the Spanish with fish
- Posh lass catches game fish — it’s arduous
- Trying porridge with fish
- Rugby in setting that’s arduous
- Demanding fish meal on top
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The straight part
We know that "hard to get through" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case hard to get through = gruelling.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 GRUELLING mean?
GRUELLING noun- (racing) A race in which the animal being raced finishes in a state of physical exhaustion.
- A gruelling ordeal.
- So difficult or taxing as to make one exhausted; backbreaking.