Synonyms for Cereal (same or very similar meaning)
WordNet sense 1 (grass whose starchy grains are used as food: wheat; rice; rye; oats; maize; buckwheat; millet):
cereal grassWordNet sense 2 (foodstuff prepared from the starchy grains of cereal grasses):
grain, food grainFrom the ODE community, based on WordNetadd/edit