The most common and most likely answer to this crossword clue is the 4 letter word YUCK
I've seen this crossword clue in The Times
Y
U
C
K
More clues leading to the result YUCK
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 YUCK mean?
YUCK noun- Something disgusting.
- The sound made by a laugh.
- Uttered to indicate disgust usually toward an objectionable taste or odour.
- To itch.