One going on foot (4)
I believe the answer is:
shoe
'going on foot' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Maybe you can see an association between them that I don't see?
'one' is the wordplay.
I cannot really see how this works, but
'one' could be 'o' (I've seen this in other clues) and 'o' is located in the answer.
The remaining letters 'she' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for shoe that I've seen before include "Case from which playing cards are delt one at a time" , "Pump, for example" , "Maybe court" , "Footwear - playing-card dispenser - part of a brake" , "Oxford, for example" .)