延髓 yánsuǐ medulla oblongata Origin Definitions Defs Strokes Stroke Words Sentences Sents 延 yán verbnoun to extend (bound form) to prolong; to stretch out; to extend in distance or time髓 suǐ noun marrow (bound form) bone marrow; tissue in the center of certain organs such as the spinal cord; pith or central tissue in plant stems