Definition
A small endocrine gland located on top of each kidney that releases hormones — most notably adrenaline (epinephrine) — in response to stress, triggering the body's fight-or-flight response by raising heart rate, blood pressure, and alertness.
Plain English
A small gland sitting on top of each kidney that pumps out stress hormones, making the heart race and the body go into alert mode when a person feels threatened or under pressure.
Context Anchor
Seen in aviation human factors discussions about normal physical reactions to stress during training, emergencies, or high-workload flying.
Derivation
From Latin 'ad-' meaning 'near' or 'on top of' and 'renes' meaning 'kidneys.' Literally 'the gland on the kidney,' which is exactly where it sits. Knowing this anchors both the location and why adrenaline is named after it.
Why Pilots Care
Stress during flight can trigger these glands, raising alertness or heart rate, so pilots learn to recognize and manage the effects for safe performance.
Grounding Statement
If a pilot is startled by a sudden problem, the adrenal glands help trigger the body’s quick “get ready to act” response.
Intuition Check
The adrenal gland is not the same thing as adrenaline. The gland is the body part; adrenaline is one of the chemicals it can release.
Example Sentence 1
When the engine sputtered on climbout, the pilot's adrenal glands flooded his system with adrenaline, sharpening his focus but also making his hands tremble on the controls.
Example Sentence 2
Instructors point out that adrenal gland responses to turbulence are normal and do not mean something is wrong.