Rodents with large cheek-pouches (8)
I believe the answer is:
hamsters
'rodents with large cheek-pouches' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for hamsters that I've seen before include "Small rodents often kept as pets" , "Mouse-like pets with cheekpouches" , "Rodents with large cheek-pouches" , "Small pet rodents with cheek-pouches" , "Rodents with large cheek pouches" .)