膝皿貝;火皿貝;石鼈;爺が背 [ひざらがい(膝皿貝;火皿貝;石鼈);じいがせ(石鼈;爺が背);ヒザラガイ] /(n) (1) (uk) chiton (any marine mollusk of the class Polyplacophora)/sea cradle/(n) (2) Japanese chiton (Acanthopleura japonica)/EntL2088080/