The most common and most likely answer to this crossword clue is the 5 letter word AFOOT
I've seen this crossword clue in The Daily Telegraph
A
F
O
O
T
More clues leading to the result AFOOT
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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 AFOOT mean?
AFOOT adjective- (predicative) That is on foot, in motion, in action, in progress.
- On foot. (means of locomotion, walking)
- On foot. (support of the body, standing)
- In motion; in action; astir; stirring; in progress.