All 4 Uses

adrenaline
in
Glass, by Ellen Hopkins
(Auto-generated)

I can almost feel the sizzle of adrenaline, pumping from the back of my skull, zooming down my spine and into my legs, making them reach for even more speed.†
*

adrenaline = “fight or flight” stimulating hormone
And that made the adrenaline pump even faster.†
I have not had an adrenaline rush since I took my little detour, one of nature's irresistible highs, denied by brain chemistry gone awry, at the claws of the monster.†

adrenaline rush = the intense feeling that comes from an increase in the "fight or flight" hormone
It defined for me exactly how crank scours the brain's pleasure center, scrubbing away dopamine, adrenaline and other natural highs.†

adrenaline = “fight or flight” stimulating hormone

Definitions:

(1) (adrenaline)
“fight or flight” stimulating hormone secreted by the adrenal gland in response to stress (making the body feel excited and ready for action)

Doctors are more likely to use the term epinephrine (possibly shortened to epi or EP). Adrenalin as a proper noun without the ending "e" is a trademark name for the same chemical.
(2) (meaning too rare to warrant focus)