The most common and most likely answer to this crossword clue is the 4 letter word FUSS
I've seen this crossword clue in The Guardian
F
U
S
S
More clues leading to the result FUSS
- Bother from unexpected source — swear initially!
- Swear changing leader will bring this trouble
- Complaint of US soldier largely ignored
- Commotion, following American warship
- Endless suffering conceals mounting trouble
- Comes together without last-minute trouble
- To-do caused by us in force, southern
- Female on the George Washington possibly causes furore
- Swear experiencing initial temperature change is hassle
- Disturbance in fine American ship
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 = fuss.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 FUSS mean?
FUSS noun- Excessive activity, worry, bother, or talk about something.
- A complaint or noise; a scene.
- An exhibition of affection or admiration.
- To be very worried or excited about something, often too much.
- To fiddle; fidget; wiggle, or adjust
- (especially of babies) To cry or be ill-humoured.
- (with over) To show affection for, especially animals.
- To pet.