ENGLISH
REFERENCE

adrenaline

n.
US //əˈdɹɛnəɫən// UK //ɐdɹˈɛnəlˌɪn// adren·a·line
  1. 1 the hormone (n.)
    B2 Upper Intermediate Technical Medicine

    a chemical in your body that makes your heart beat faster when you are stressed or excited.

    the hormone epinephrine, secreted by the adrenal glands, which increases cardiac output and raises glucose levels in the blood.

    Example

    The doctor gave him a shot of adrenaline to stop the allergic reaction.

    Example

    Adrenaline is released into the bloodstream during the fight-or-flight response, preparing the body for immediate physical exertion.

    Usage

    Often used as an uncountable noun in medical contexts.
  2. 2 excitement (n.)
    B2 Upper Intermediate

    a feeling of great energy and excitement.

    a state of heightened physiological arousal or intense excitement.

    Example

    I felt a rush of adrenaline as I stood at the top of the mountain.

    Example

    Extreme sports enthusiasts often seek the adrenaline hit that comes from activities like skydiving or rock climbing.

    Usage

    Commonly used in the phrase 'adrenaline rush'.
Origin

From adrenal + -ine, coined by Japanese chemist Takamine Jōkichi in 1901.

Idioms1 entry

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