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

• boost
• encouragement
• goad
• impetus
• impulse
• incentive
• incitation
• incitement
• instigation
• momentum
• motivation
• provocation
• spur
• stimulant
• yeast

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

Chinese factory activity contracted at its fastest pace in 16 months in April, adding urgency to Beijing’s efforts to roll out fresh economic stimulus. —Nectar Gan, CNN Money, 12 May 2025

Justin Sullivan | Getty Images China’s exports surged in April even as businesses bore the brunt of U.S. tariffs that kicked into higher gear last month, while imports narrowed declines as Beijing stepped up stimulus. —Chloe Taylor,holly Ellyatt, CNBC, 9 May 2025

The brain’s ability to process information can slow after cannabis use, so the abundance of outdoor stimuli may intensify the psychoactive effects, making the experience feel richer and more immersive. —Tribune Content Agency, Mercury News, 9 May 2025

Given the significant economic disruptions accompanying recent international trade tensions, substantial stimulus investment in sustainable infrastructure, including commercial real estate, could deliver multifaceted societal benefits. —Ali Hoss, Forbes.com, 7 May 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