stimulus

noun

stim·​u·​lus ˈstim-yə-ləs How to pronounce stimulus (audio)
plural stimuli ˈstim-yə-ˌlī How to pronounce stimulus (audio) -ˌlē How to pronounce stimulus (audio)
Synonyms of stimulus
: something that rouses or incites to activity: such as
a
: incentive
b
: stimulant sense 1
c
: an agent (such as an environmental change) that directly influences the activity of a living organism or one of its parts (as by exciting a sensory organ or evoking muscular contraction or glandular secretion)

Synonyms of stimulus

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Examples of stimulus in a Sentence

The pay raise was a stimulus for production. Heat and light are physical stimuli. The dog responded to the stimulus of the ringing bell.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Studies show that the brain continues to learn when exposed to novel situations and stimuli. — Dr. Deepika Chopra, Flow Space, 16 June 2026 But if productivity growth is low, then stimulus just turns into inflation—too many dollars chasing too few goods. — Bill Conerly, Forbes.com, 30 June 2026 Lower body weight means less mechanical load on the skeleton — reducing the stimulus for bones to stay strong, Kennel explained. — The Washington Post, San Diego Union-Tribune, 9 June 2026 Keep in mind, however, that what is considered challenging varies by person—for some, a run or a forceful stair climb can provide that stimulus, while for others, walking can be enough. — Currie Engel, Health, 23 June 2026 See All Example Sentences for stimulus

Word History

Etymology

Latin

First Known Use

1684, in the meaning defined above

Time Traveler
The first known use of stimulus was in 1684

Rhymes for stimulus

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Browse Nearby Words

stimulogenous
stimulus
stimulus diffusion
See all Nearby Words

Cite this Entry

“Stimulus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/stimulus. Accessed 7 Jul. 2026.

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Kids Definition

stimulus

noun
stim·​u·​lus ˈstim-yə-ləs How to pronounce stimulus (audio)
plural stimuli -ˌlī How to pronounce stimulus (audio)
-ˌlē
1
: something that rouses or stirs to action : incentive
2
: something (as an environmental change) that acts to partly change bodily activity (as by exciting a sensory organ)
heat, light, and sound are common physical stimuli

Medical Definition

stimulus

noun
stim·​u·​lus ˈstim-yə-ləs How to pronounce stimulus (audio)
plural stimuli -ˌlī How to pronounce stimulus (audio) -ˌlē How to pronounce stimulus (audio)
1
: stimulant sense 1
2
: an agent (as an environmental change) that directly influences the activity of living protoplasm (as by exciting a sensory organ or evoking muscular contraction or glandular secretion)
a visual stimulus

More from Merriam-Webster on stimulus

Nglish: Translation of stimulus for Spanish Speakers

Britannica.com: Encyclopedia article about stimulus

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