S: (n) yolk, vitellus (nutritive material of an ovum stored for the nutrition of an embryo (especially the yellow mass of a bird or reptile egg))
S: (n) comfort food (food that is simply prepared and gives a sense of wellbeing; typically food with a high sugar or carbohydrate content that is associated with childhood or with home cooking)
S: (n) adulterant, adulterator (any substance that lessens the purity or effectiveness of a substance) "it is necessary to remove the adulterants before use"
S: (n) fomentation (a substance used as a warm moist medicinal compress or poultice)
S: (n) fuel (a substance that can be consumed to produce energy) "more fuel is needed during the winter months"; "they developed alternative fuels for aircraft"
S: (n) humectant (any substance that is added to another substance to keep it moist)
S: (n) inoculant, inoculum (a substance (a virus or toxin or immune serum) that is introduced into the body to produce or increase immunity to a particular disease)
S: (n) jelly (any substance having the consistency of jelly or gelatin)
S: (n) leaven, leavening (a substance used to produce fermentation in dough or a liquid)
S: (n) refrigerant (any substance used to provide cooling (as in a refrigerator))
S: (n) lysin (any substance (such as an antibody) or agent that can cause lysis)