Rodent close to quite large animal (5)
I believe the answer is:
ratel
'animal' is the definition.
(I know that ratel is a type of animal)
'rodent close to quite large' is the wordplay.
'rodent' becomes 'rat' (rat is a kind of rodent).
'close to' says to take the final letters (the close/ending of).
'large' becomes 'L' (eg in clothes sizes).
The final letter of 'quite' is 'e'.
'rat'+'e'+'l'='RATEL'
(Other definitions for ratel that I've seen before include "Badger-like mammal" , "Mammal's" , "Honey-badger" , "predator" , "animal like a badger" .)