Adrenaline
noun /əˈdrɛn.ə.lɪn/ — The stress hormone that triggers fight-or-flight; surge of energy
Definition
A hormone produced by the adrenal glands in response to stress, danger, or intense excitement — accelerating heart rate, expanding airways, releasing glucose. Adrenaline is the body's emergency fuel.
Beyond the definition
Adrenaline is the body's honest assessment of the situation: something is happening that requires your full capacity. The surge is indiscriminate — it cannot tell a real threat from a performance, a first kiss from a near-accident.
Origin & history
Latin: ad (near, at) + renes (kidneys). The adrenal glands sit near the kidneys — the word names their location. Also known as epinephrine in American medical usage.
Example sentences
Illustrative sentences for learning, not verified community posts or sourced quotations.
The adrenaline hit her before she knew what was happening — the body knew first.
Adrenaline junkies chase the feeling because it's the most alive the body knows how to feel.
After the crisis, the adrenaline crash is as real as the surge.
Synonyms
epinephrine, fight-or-flight hormone, stress hormone
Related words
Adrenaline vs epinephrine
Adrenaline and epinephrine are the same chemical. Adrenaline is commonly used in British and general English, while epinephrine is the standard in American medical terminology.
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Word in the Wild
See how this word appears in life, language and stories.
Illustrative sentences and imagined stories for learning — not verified sightings, interviews, or sourced quotations.
Fictional scene
Entering with Focused Intensity
An adult stands at a forest entrance holding a glowing, illuminating talisman.
The glowing talisman and the transition from light to shadow mirror the surge of adrenaline during a moment of high anticipation. Just as adrenaline acts as emergency fuel, the talisman provides focus and readiness for the threshold ahead.
Image credit: Wordspun · AI-generated conceptual illustration