The most common and most likely answer to this crossword clue is the 3 letter word WHY
W
H
Y
More clues leading to the result WHY
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 WHY mean?
WHY noun- Reason
- For what cause, reason, or purpose (interrogative adverb).
- For which cause, reason, or purpose (relative adverb).
- An exclamation used to express indignation, mild surprise, or impatience.
- A young heifer.