The most common and most likely answer to this crossword clue is the 3 plus 4 letter word HAY WAIN
I've seen this crossword clue in The Daily Telegraph
H
A
Y
W
A
I
N
More clues leading to the result HAY WAIN
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.