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stimulant

American  
[stim-yuh-luhnt] / ˈstɪm yə lənt /

noun

  1. Physiology, Medicine/Medical. something that temporarily quickens some vital process or the functional activity of some organ or part.

    Adrenalin is a stimulant for the heart.

  2. any food or beverage that stimulates, especially coffee, tea, or, in its initial effect, alcoholic liquor.

  3. a stimulus or incentive.


adjective

  1. Physiology, Medicine/Medical. temporarily quickening some vital process or functional activity.

  2. stimulating.

stimulant British  
/ ˈstɪmjʊlənt /

noun

  1. a drug or similar substance that increases physiological activity, esp of a particular organ

  2. any stimulating agent or thing

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

adjective

  1. increasing physiological activity; stimulating

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
stimulant Scientific  
/ stĭmyə-lənt /
  1. An agent, especially a drug, that causes increased activity, especially of the nervous or cardiovascular systems. Caffeine is a commonly used stimulant.


Other Word Forms

  • antistimulant adjective
  • nonstimulant noun

Etymology

Origin of stimulant

First recorded in 1720–30, stimulant is from the Latin word stimulant- (stem of stimulāns, present participle of stimulāre to goad). See stimulus, -ant

Explanation

A stimulant is a drug that speeds up your body or an event that spurs you to action. Both types of stimulant get you going. You might drink coffee in the morning for a reason: the caffeine in coffee is a stimulant, which gives you energy and helps you wake up. Other stimulants are much more harmful, such as illegal drugs like cocaine, but all stimulants speed up your system. Also, a stimulant can be anything that arouses action. When Pearl Harbor was attacked, it was a stimulant that drove America into World War II.

Keep Reading on Vocabulary.com

Vocabulary lists containing stimulant

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Current treatments for attention disorders typically increase excitatory signaling in prefrontal brain circuits using stimulant medications.

From Science Daily • Jan. 2, 2026

Of these, about 22,000 hectares are legal -- grown to be chewed as a stimulant, brewed into a tea thought to combat altitude sickness or used in religious rituals.

From Barron's • Nov. 21, 2025

When he was 11, Tyrell Cooley was taking a very high dose of Concerta, along with guanfacine, sometimes used as an adjunct to a stimulant, at night.

From The Wall Street Journal • Nov. 20, 2025

More than 10 traders were arrested last Friday in the main coastal city of Mombasa as the ban on the stimulant took effect, local media reported.

From BBC • May 28, 2024

It was their delight, their folly, their anodyne, their intellectual stimulant.

From "1984" by George Orwell