The most common and most likely answer to this crossword clue is the 4 letter word WONK
I've seen this crossword clue in Independent
W
O
N
K
More clues leading to the result WONK
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 WONK mean?
WONK noun- An overly studious person, particularly student.
- (by extension) A policy wonk or other intellectual expert.