Beastly medic hides in duvets (3)
I believe the answer is:
vet
'beastly medic' is the definition.
The answer and definition can be both people as well as being singular nouns.
Maybe you can see a link between them that I don't see?
'hides in duvets' is the wordplay.
'hides in' indicates the answer is hidden within the clue (I've seen 'hidden in' mean this).
'VET' is hidden within 'duvets'.
Can you help me to learn more?
(Other definitions for vet that I've seen before include "Critically examine" , "A small animal doctor" , "Scrutinise" , "Animal doctor, in brief" , "Ex-serviceman" .)