Source : Webster's Revised Unabridged Dictionary (1913)

Adrenaline \Ad*re"nal*ine\, n. Also Adrenalin \Ad*re"nal*in\
   (Physiol. Chem.)
   A crystalline substance, {C9H13O3N}, obtained from suprarenal
   extract, of which it is regarded as the active principle. It
   is used in medicine as a stimulant and hemostatic.

Source : WordNet®

adrenaline
     n : a catecholamine secreted by the adrenal medulla in response
         to stress (trade name Adrenalin); stimulates autonomic
         nerve action [syn: {epinephrine}, {epinephrin}, {Adrenalin}]