The most common and most likely answer to this crossword clue is the 4 letter word COOT
I've seen this crossword clue in The Guardian
C
O
O
T
More clues leading to the result COOT
- Duck in bed or some other bird
- A rail company motto: “every second counts”
- Bird making bird sound at end of flight
- Hurry to shave head – so a baldie?
- Waterbird on edge of the Camargue also turned up
- No baby sleeping here, apparently
- Bill’s partner by the end of August is 8 bald
- Bill’s other half cut it – silly
- Fool could make love in bed
- Rail firm motto: every second counts!
Buddy explains!

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 COOT mean?
COOT noun- Any of various aquatic birds of the genus Fulica that are mainly black with a prominent frontal shield on the forehead.
- A foolish or eccentric fellow
- (with the) A success; something excellent.
- Body louse (Pediculus humanus).