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allergy - n. a medical condition that causes someone to become sick after eating, touching, or breathing something that is harmless to most people
reversal - n. a change to an opposite state, condition, decision, etc.
pediatrician - n. a doctor who treats babies and children
swell - v. to become larger than normal
epinephrine - n. a kind of medication that is used in emergencies to treat serious allergic reactions to insects, foods, drugs or other substances.
introduce - v. to make (someone) known to someone else by name
assume - v. to think that something is true or probably true without knowing that it is true
