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 of stimulus

• 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

But any economic stimulus program runs the risk of causing inflation to spike, and many economists believe the pandemic-era stimulus was at least partially responsible for the rise in consumer prices that ensued over the following years. — Joe Walsh, CBS News, 10 Sep. 2026

The edit intercuts old film reels, both archival B-roll and seeming home movies, to hint at how all these new stimuli jog Brooke’s memory. — Marshall Shaffer, IndieWire, 9 Sep. 2026

Rather than explaining behavior solely in terms of observable stimuli and responses, cognitive psychologists investigated ways in which individuals acquire, organize, store, and use information. — Encyclopedia Britannica, 8 Sep. 2026

That’s as governments since the COVID pandemic have continued spending as if borrowing costs were still at crisis-era lows and letting deficits worsen as if their economies were still in desperate need of emergency stimulus. — Jason Ma, Fortune, 6 Sep. 2026

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