The most common and most likely answer to this crossword clue is the 7 letter word SHELLED
I've seen this crossword clue in The Guardian
S
H
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More clues leading to the result SHELLED
Buddy explains!
The straight part
We know that "Under fire/as nuts may be" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case under fire/as nuts may be = shelled.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 SHELLED mean?
SHELLED verb- To remove the outer covering or shell of something.
- To bombard, to fire projectiles at, especially with artillery.
- To disburse or give up money, to pay. (Often used with out).
- To fall off, as a shell, crust, etc.
- To cast the shell, or exterior covering; to fall out of the pod or husk.
- To switch to a shell or command line.
- To form shallow, irregular cracks (in a coating).
- To form a shelling.
- (often in combination) Having a shell; testaceous.
- Having had the shell removed.
- Unable to keep up in a race, having used up one's reserves of energy.