核糖核酸 hétánghésuān RNA Definitions Defs Origin Strokes Stroke Words Sentences Sents 核糖 hétáng ribose (bound form) a type of five-carbon sugar that is a key component of 核糖核酸 hétánghésuān核酸 hésuān nucleic acid An organic compound found in the cells of all living things and viruses, essential for growth, reproduction, and heredity.