stimulus

noun

stim·​u·​lus ˈstim-yə-ləs 

plural stimuli ˈstim-yə-ˌlī  -ˌlē 

: 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

• incentive
• impetus
• encouragement
• motivation

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

Will stimulus checks be sent as part of Trump's 'Big, Beautiful Bill?' No. —Cailey Gleeson, jsonline.com, 31 July 2025

What seems clear is that by some genetic predisposition that remains invisible to us, the neural latticework designed to interpret, modulate, and respond to stimuli is prone to going haywire in some people, causing a cascade of changes that very often results in head pain. —Tom Zeller Jr. july 30, Literary Hub, 30 July 2025

In early 2021, after trading on the app exploded thanks in part to pandemic lockdowns and millions of stimulus checks, Robinhood became the focus of a regulatory firestorm during the GameStop meme-stock trading frenzy. —Nina Bambysheva, Forbes.com, 29 July 2025

Nathan Howard | Reuters Sen. Josh Hawley, R-Mo., on Monday introduced a bill to send tariff rebate checks to American families, which would be similar to the stimulus checks sent during the Covid-19 pandemic. —Lorie Konish,kate Dore, Cfp®, Ea, CNBC, 29 July 2025

Word History

Etymology

Latin

First Known Use

1684, in the meaning defined above

Rhymes for stimulus

• limulus

Kids Definition

stimulus

noun

stim·​u·​lus ˈstim-yə-ləs 

plural stimuli -ˌlī 

-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 

plural stimuli -ˌlī  -ˌlē 

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