possum /ˈpɒsəm/noun 2verb 1forms 4phrases 1 noun2 •A marsupial of several families of the order Diprotodontia, found in Australia and neighboring islands. •(US) An opossum, a marsupial of the family Didelphidae of the Americas. verb1 •To play possum; to feign sleep, illness, or death. formspossumed · possuming · possums · possa Phrases with possum play possumTo feign death; to remain quiet and still to escape attention or remain undetected; to lie low.