Nation short of a feature (4)
I believe the answer is:
chin
'feature' is the definition.
(chin is a kind of feature)
'nation short of a' is the wordplay.
'nation' becomes 'china' (China is an example).
'short of' suggests deleting specific letters.
'china' with 'a' taken away is 'CHIN'.
(Other definitions for chin that I've seen before include "part of mug" , "Facial feature" , "Bottom part of jaw" , "hit" , "narrow opening" .)