The most common and most likely answer to this crossword clue is the 6 letter word CHAFED
C
H
A
F
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D
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The straight part
We know that "Nettled" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case nettled = chafed.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 CHAFED mean?
CHAFED verb- To excite heat in by friction; to rub in order to stimulate and make warm.
- To excite passion or anger in; to fret; to irritate.
- To fret and wear by rubbing.
- To rub; to come together so as to wear by rubbing; to wear by friction.
- To be worn by rubbing.
- To have a feeling of vexation; to be vexed; to fret; to be irritated.