A stiffener for the big-headed individual (4)
I believe the answer is:
bone
'a stiffener' is the definition.
The definition and answer can be both substances as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'big-headed individual' is the wordplay.
'big-headed' becomes 'b' (this could be a standard abbreviation which I don't know about).
'individual' becomes 'one' (an individual is one person).
'b'+'one'='BONE'
'for the' is the link.
Can you help me to learn more?
(Other definitions for bone that I've seen before include "Skeleton component" , "#Close to it is risque" , "How dry" , "Carpal or tarsal, for example" , "Skeleton material" .)