The most common and most likely answer to this crossword clue is the 3 letter word EKE
I've seen this crossword clue in Independent
E
K
E
More clues leading to the result EKE
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 EKE mean?
EKE noun- (obsolete except Britain) An addition.
- A small stand on which a beehive is placed.
- A spacer put between or over or under hive parts to make more space: see http//www.dave-cushman.net/bee/eke.html
- Chiefly in the form eke out: to add to, to augment; to increase; to lengthen.
- Also; in addition to.