Very large mammal (8)
I believe the answer is:
elephant
'very large mammal' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for elephant that I've seen before include "it's said to have lots of memory" , "Pachyderm hunted for ivory" , "Jumbo" , "Large land mammal" , "The plane (anag.)" .)