Won't it stay put on your foot? (7)

I believe the answer is:

slipper

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'foot?' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe there's an association between them I don't understand?

I cannot understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for slipper that I've seen before include "Type of footwear" , "pump" , "Nearby; pub" , "Casual footwear" , "Footwear item" .)

I've seen this clue in the Evening Standard.

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