ENGLISH
REFERENCE

epinephrine

n. uncountable
C1 Advanced US //ˌɛpɪˈnɛfɹɪn// UK //ˈɛpɪnˌɛfɹiːn// ep·i·neph·rine

n. a hormone and medicine that your body makes when you are in danger. It helps your heart beat faster and makes your body ready to run or fight.

n. a hormone and neurotransmitter secreted by the adrenal medulla in response to stress. It functions as a medication to treat anaphylaxis and cardiac arrest by increasing heart rate and blood pressure.


SIMPLE

The doctor gave the patient an injection of epinephrine.

CONTEXTUAL

Patients with severe allergies carry an epinephrine auto-injector to manage life-threatening reactions immediately.

COMPLEX

The sudden release of epinephrine during a traumatic event triggers the fight-or-flight response, redirecting blood flow to the muscles and increasing glucose levels in the bloodstream.

Synonyms
Origin

From Ancient Greek ἐπι- (epi-, “upon”) + νεφρός (nephrós, “kidney”) + -ine.

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