分子遗传学 fēnzǐyíchuánxué molecular genetics Origin Definitions Defs Strokes Stroke Words Sentences Sents 分子 fēnzǐ noun molecule The smallest unit of a chemical compound that retains its chemical properties.遗传学 遺傳學 yíchuánxué genetics the scientific study of genes, heredity, and how traits are passed from parents to children