Definition of "stimulant" [stim•u•lant]

• An agent, especially a chemical agent such as caffeine, that temporarily arouses or accelerates physiological or organic activity. (noun)
• A stimulus or an incentive: "An age of political excitement is usually a stimulant to literature” ( Will Durant). (noun)
• A food or drink, especially an alcoholic drink, believed to have a stimulating effect. (noun)
• Serving as or being a stimulus; stimulating. (adjective)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "We take a solution of what we call a stimulant and immerse the bioplasm in it, and we find that it increases its activity, moves faster, takes up more pabulum, and divides more rapidly than in the unstimulated condition."
• "But the eye-opening stimulant is found in lots of other beverages, and even some food and medications."
• "In similar ways to stimulant drugs such as amphetamine, clenbuterol can have short-term stimulant effects, including increasing aerobic capacity, blood pressure and alertness."