内ない乳にゅうないにゅうMeanings1nounendospermbotanyBotanical term for the nutrient-rich tissue inside seeds that nourishes the developing embryo.イネの種しゅ子しでは、内ない乳にゅうが主おもにデンプンから成なる。In rice seeds, the endosperm is mainly composed of starch.