o·pos·sum 
(ə-pŏsəm, pŏsəm)
(ə-pŏsəm, pŏsəm)n. pl. opossum or o·pos·sums
1. Any of various nocturnal, usually arboreal marsupials of the family Didelphidae of the Americas, especially Didelphis virginiana of North and Central America, having a thick coat, a long snout, and a long prehensile tail. See Note at tater.
2. A possum of Australia and adjacent islands.
[Virginia Algonquian.]
opossumadult female opossum, Didelphis virginiana, transporting offspring on her back