(1):
(a.) Produced increased vital action in the organism, or in any of its parts.
(2):
(a.) Serving to stimulate.
(3):
(n.) That which stimulates, provokes, or excites.
(4):
(n.) An agent which produces a temporary increase of vital activity in the organism, or in any of its parts; - sometimes used without qualification to signify an alcoholic beverage used as a stimulant.