老鼠药 lǎoshǔyào rat poison Origin Definitions Defs Strokes Stroke Words Sentences Sents 老 lǎo noun [animal prefix] Prefix used in the common names of certain animals.鼠 shǔ noun rat (bound form) rat; mouse; any of various small rodents药 藥 yào noun medicine medicine; drug; substance used to treat disease or kill pests