Low dull noise (coming from the stomach?) (6)

I believe the answer is:

rumble

(Other definitions for rumble that I've seen before include "Utter in deep voice, of have a slang fight - in the jungle?" , "Discover (illicit activity); continuous deep noise" , "Thunder, perhaps" , "Harlem gangs might" , "Find out the truth" .)

I've seen this clue in The Guardian.

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