Thick-skinned herbivore (5)
I believe the answer is:
rhino
'thick-skinned herbivore' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for rhino that I've seen before include "Funds" , "Massive mammal with one or two horns on its nose, in short" , "In brief, large thick-skinned animal of Africa" , "wild beast" , "Large African pachyderm" .)