French not accepting width in feet (4)
I believe the answer is:
paws
'feet' is the definition.
(I know this)
'french not accepting width' is the wordplay.
'french not' becomes 'pas' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'accepting' is an insertion indicator (inserted letters are accepted).
'width' becomes 'w' (abbreviation in geometry).
'pas' going around 'w' is 'PAWS'.
'in' acts as a link.
Can you help me to learn more?
(Other definitions for paws that I've seen before include "Feet of a quadruped" , "Parts of Cats" , "Tom's feet" .)