The most common and most likely answer to this crossword clue is the 7 letter word SCIATIC
S
C
I
A
T
I
C
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The straight part
We know that "Referring to nerve" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case referring to nerve = sciatic.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 SCIATIC mean?
SCIATIC noun- A person with sciatica.
- Of, or relating to the ischium.
- Of, or relating to sciatica.