komori-nezumi means "Opossum" in English.

  • In some places, the words Possum and Opossum are synonymous. In other places, however, Possum refers to animals of the suborder Phalangeriformes while Opossum refers to animals of the order Didelphimorphia.
komori-nezumi written with kanji is 子守鼠.
This word contains non-jouyou kanji 常用漢字.
komori-nezumi written with katakana is コモリネズミ.
komori-nezumi written with hiragana is こもりねずみ.
Romaji ko mo ri ne zu mi
Meaning Babysitter Rat
School Level 小1 小3

Further Reading

Wikipedia: オポッサム (Opossum)