Definition

1. Noun:
   • A hormone and neurotransmitter: Adrenalin is a substance produced by the adrenal glands, especially in response to stress, fear, or excitement. It prepares the body for rapid action by increasing heart rate, blood pressure, and energy supplies.
   • A specific drug: Adrenalin is also the trade name for a synthetic form of this hormone, used as a medication in emergencies, such as severe allergic reactions.

Examples of Usage

• Noun:
  • The sudden scare caused a rush of adrenalin. (The sudden scare caused the body to release this hormone.)
  • The doctor administered an injection of Adrenalin to treat the anaphylactic shock. (The doctor used the specific drug for emergency treatment.)

Advanced Usage

• "Adrenalin rush" or "adrenaline rush": A sudden, intense feeling of excitement and energy caused by the release of this hormone.
  • Skydiving gives me an incredible adrenalin rush.
• "Adrenalin junkie" (informal): A person who seeks out dangerous or thrilling activities for the excitement they provide.
  • He's a real adrenalin junkie, always looking for the next extreme sport.

Variants and Related Words

• Adrenaline: This is the more common, non-trademark spelling used in general contexts, especially in British English. The meanings are identical to "adrenalin".
  • The news sent her adrenaline levels soaring.
• Adrenergic (adj): Relating to or denoting nerve cells that use adrenalin (or noradrenaline) as a neurotransmitter.
  • Adrenergic receptors respond to stress hormones.

Synonyms

• Epinephrine: This is the official scientific and medical name for the same hormone and drug. "Adrenalin/Adrenaline" and "epinephrine" are used interchangeably, with "epinephrine" being more common in American medical contexts.
  • The EpiPen auto-injector contains epinephrine.

Notes on Meaning

• The word primarily refers to a natural biochemical substance produced by the body.
• With a capital 'A' (Adrenalin), it specifically refers to the trademarked drug product.
• The feelings of excitement, heightened awareness, and increased strength in stressful situations are commonly attributed to the effects of this hormone.

Noun

1. a catecholamine secreted by the adrenal medulla in response to stress (trade name Adrenalin); stimulates autonomic nerve action