inheres in role material entity nutrient role 19 Feb 2009; old def: A nutrient role is a role played by a substance used in an organism's metabolism which is taken in from the environment and provides nourishment. nutrient nutrient role GROUP: Role branch Luria broth; vitamin A; A nutrient is a substance used in an organism's metabolism which must be taken in from the environment. Wikipedia. Wikipedia, feb 29, 2008 a role that inheres in a material entity and is realized in the use of that material entity by an organism when it is used in that organism's metabolism and provides nourishment. metadata complete