The most common and most likely answer to this crossword clue is the 8 letter word SCIATICA
I've seen this crossword clue in The Guardian
S
C
I
A
T
I
C
A
More clues leading to the result SCIATICA
- Nervous complaint: spies twitch it has introduced
- Asiatic cooks taking cocaine for painful condition
- Ache with cold during Asiatic storm
- Special US agency receiving a jerk’s complaint
- Complaint from jerk in small Channel Islands group trying to keep dry
- Science in brief: a spasm accompanies a form of neuritis
- Complaint nieces regularly raised, discussing historic Greece
- Cold Asiatic’s beaten pain
- Act is rudely interrupted by agents, which is a pain
Buddy explains!

The straight part
We know that "complaint" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case complaint = sciatica.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 SCIATICA mean?
SCIATICA noun- Neuralgia of the sciatic nerve, characterised by pain radiating down through the buttocks and the back of the thigh.