stim·​u·​lus | \ ˈstim-yə-ləs How to pronounce stimulus (audio) \
plural stimuli\ ˈstim-​yə-​ˌlī How to pronounce stimuli (audio) , -​ˌlē \

Definition of stimulus

: something that rouses or incites to activity: such as
a : incentive
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)

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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.
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Recent Examples on the Web

Lollapalooza, with its back-to-back lineup, is an uninterrupted wave of stimuli, with attendees screaming, cheering and singing along to their favorite artists. Chicago Tribune Staff,, "Daywatch: A rare look at Chicago’s entrenched gun culture, post-Lollapalooza depression and other things to know to start your day," 6 Aug. 2019 So my art became my body’s automatic response to stimuli, whether that is a specific person, place, or event. Chris Triunfo,, "Meghan Kausel," 1 Aug. 2019 In the study, the scientists placed an elastomer in between two electrodes, which activate with an electrical stimulus (provided by the human eye). Daisy Hernandez, Popular Mechanics, "These Contact Lenses Zoom In and Out with the (Double) Blink of an Eye," 29 July 2019 The likelihood of another giant stimulus, routine in the past whenever growth slowed, is lower this time. The Economist, "China’s growth is the slowest in nearly three decades: get used to it," 18 July 2019 Therefore, any form of fiscal stimulus, which will worsen fiscal deficit, is not desirable. Vk Vijayakumar, Quartz India, "A fragile economy leaves Nirmala Sitharaman with little room to dole out goodies," 1 July 2019 Doctors now deliver shorter pulses of electricity, which reduces the brain’s exposure to the stimulus, and place electrodes on only the right side of the head instead of both, lessening potential memory loss. Sumathi Reddy, WSJ, "New Thinking Challenges the Stigma Around ‘Shock Therapy’," 30 June 2019 Help learn triggers Migraines are often triggered by environmental stimuli, like bright lights, loud noises or certain foods. Nadia Suleman, Time, "5 Ways to Help a Friend or Loved One Who Suffers From Migraines," 28 June 2019 It can be induced by a variety of stimuli, or, in the term commonly used in ASMR-speak, triggers. Annie Vainshtein,, "Everything you ever wanted to know about ASMR," 27 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'stimulus.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of stimulus

1684, in the meaning defined above

History and Etymology for stimulus


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Statistics for stimulus

Last Updated

7 Sep 2019

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Time Traveler for stimulus

The first known use of stimulus was in 1684

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More Definitions for stimulus



English Language Learners Definition of stimulus

: something that causes something else to happen, develop, or become more active
: something that causes a change or a reaction


stim·​u·​lus | \ ˈsti-myə-ləs How to pronounce stimulus (audio) \
plural stimuli\ -​ˌlī , -​ˌlē \

Kids Definition of stimulus

1 : something that stirs or urges to action The reward was a stimulus for greater effort.
2 : an influence that acts usually from outside the body to partly change bodily activity (as by exciting a receptor or sense organ) Light, heat, and sound are common physical stimuli.


stim·​u·​lus | \ ˈstim-yə-ləs How to pronounce stimulus (audio) \
plural stimuli\ -​ˌlī How to pronounce stimuli (audio) , -​ˌlē How to pronounce stimuli (audio) \

Medical Definition of stimulus

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

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Comments on stimulus

What made you want to look up stimulus? Please tell us where you read or heard it (including the quote, if possible).


formidable, illustrious, or eminent

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