Fido's foot (3)
I believe the answer is:
paw
'fido's foot' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for paw that I've seen before include "Hand; foot" , "Eg, a dog's foot" , "Mammal's foot" , "Cat's foot" , "Manhandle" .)