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epidemiology – n. medical : the study of how disease spreads and can be controlled
mortality – n. the number of deaths that occur in a particular time or place
appetite – n. a physical desire for food
nutrient – n. a substance that plants, animals, and people need to live and grow
omega-3 – n. science essential fatty acids that are found in fish, green leafy vegetables and some nuts and vegetable oils
substitute – n. a person or thing that takes the place of someone or something else
