Guineapig-like rodent (7)

I believe the answer is:

hamster

(Other definitions for hamster that I've seen before include "Small pet rodent with pouched cheeks" , "Rodent often kept as pet" , "Rodent with large cheek pouches" , "Short-tailed burrowing rodent" , "Little beast" .)

I've seen this clue in the Sydney Morning Herald.

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