The most common and most likely answer to this crossword clue is the 9 letter word CARBONADO
C
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B
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The straight part
We know that "stew" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case stew = carbonado.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 CARBONADO mean?
CARBONADO noun- Meat or fish that has been scored and broiled.
- To make a carbonado of; to score and broil.
- To cut or hack, as in combat.
- A dark, non-transparent, impure form of polycrystalline diamond (also containing graphite and amorphous carbon) used in drilling.