The most common and most likely answer to this crossword clue is the 5 letter word CLUE?
I've seen this crossword clue in The Guardian
C
L
U
E
?
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 CLUE? mean?
CLUE? noun- A strand of yarn etc. as used to guide one through a labyrinth; something which points the way, a guide.
- Information which may lead one to a certain point or conclusion.
- An object or a kind of indication which may be used as evidence.
- Insight or understanding ("to have a clue [about]" or "to have clue". See have a clue, clue stick)
- To provide with a clue.
- To provide someone with information which he or she lacks (often used with "in" or "up").