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

Policymakers have signaled a longer-term push to lift consumption and tech self-reliance but have avoided major new stimulus as the economy remains on track to meet its 5% growth target. —Victor Loh, CNBC, 30 Nov. 2025

The parks are also working with the International Board of Credentialing and Continuing Education Standards to ensure the rides are scored for various sensory stimuli. —Eve Chen, USA Today, 28 Nov. 2025

Productivity is starting to improve as firms adopt AI, software and new processes, generating growth without external stimulus. —Phillip Molnar, San Diego Union-Tribune, 27 Nov. 2025

Creating that peace begins with removing unnecessary stimuli — no artificial sound, scent, or light, and no visual clutter to distract the senses. —Eileen Falkenberg-Hull, MSNBC Newsweek, 26 Nov. 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