#yolk__vitellus  nutritive material of an ovum stored for the nutrition of an embryo (especially the yellow mass of a bird or reptile egg)
  supertype:  #food_or_beverage__nutrient__food  any substance that can be metabolized by an organism to give energy and build tissue
  part of:  #egg  animal reproductive body consisting of an ovum or embryo together with nutritive and protective envelopes; especially the thin-shelled reproductive body laid by e.g. female birds

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