stimulus

American  

[stim-yuh-luhs] / ˈstɪm yə ləs /

noun

plural

stimuli

1. something that incites to action or exertion or quickens action, feeling, thought, etc..

   The approval of others is a potent stimulus.

   Synonyms:

   provocation, motive, enticement, incitement

   Antonyms:

   discouragement

2. Physiology, Medicine/Medical. something that excites an organism or part to functional activity.

   Synonyms:

   stimulant

---

stimulus British  

/ ˈstɪmjʊləs /

noun

1. something that stimulates or acts as an incentive

2. any drug, agent, electrical impulse, or other factor able to cause a response in an organism

3. an object or event that is apprehended by the senses

4. med a former name for stimulant

---

stimulus Scientific  

/ stĭm′yə-ləs /

plural

stimuli

1. Physiology Something that can elicit or evoke a physiological response in a cell, a tissue, or an organism. A stimulus can be internal or external. Sense organs, such as the ear, and sensory receptors, such as those in the skin, are sensitive to external stimuli such as sound and touch.

2. Something that has an impact or an effect on an organism so that its behavior is modified in a detectable way.

3. See more at classical conditioning

---

stimulus Cultural  

1. plur. stimuli (stim-yuh-leye) An action, condition, or person that provokes a response, especially a conditioned response.

---

Usage

What does stimulus mean? In general, a stimulus is something that provokes or causes an action or response, as in Failing that test was the stimulus I needed to start studying harder.The plural of stimulus is stimuli. Its verb form is stimulate, which typically means to spur into action or to invigorate.In the context of science, a stimulus is anything that makes an organism or a part of an organism react in some way. For example, for most plants, sunlight acts as a stimulus that causes (stimulates) them to grow or move toward it.In economics, a stimulus is an injection of money into an economy by a government that’s intended to spur (stimulate) economic growth. This can take many forms, such as giving money directly to citizens via stimulus checks. In this sense, stimulus is usually used in the singular, especially in phrases like economic stimulus, stimulus package, and stimulus plan.Example: Congress has passed an unprecedented stimulus package in response to the 2020 coronavirus pandemic in the hopes of stimulating the economy at a time when so many people have lost income due to being out of work.

Other Word Forms

• interstimulus noun
• poststimulus adjective
• prestimulus noun
• understimulus noun

Etymology

Origin of stimulus

First recorded in 1605–15; from Latin: “a goad”

Example Sentences

With pandemic-era stimulus initiatives long forgotten, home prices plateauing, and investor portfolios pointing down, consumer sentiment has little reason to improve.

From Barron's • Apr. 2, 2026

In 2022, household consumption was lifted by multiple tailwinds, including job growth coming out of the Covid-19 pandemic, vestiges of government stimulus in response to the pandemic-related downturn, and strong household balance sheets.

From Barron's • Apr. 2, 2026

It was only after the start of the Covid-19 pandemic, which brought stimulus checks and rising home values, that average wealth turned positive for the bottom 50% of households again.

From The Wall Street Journal • Mar. 25, 2026

But even a small pullback in Gulf spending, reoriented from U.S. businesses—like Oracle and Paramount—toward the domestic buildup of defense capacity and economic stimulus, would leave the Ellisons without billions of dollars in needed funds.

From Slate • Mar. 20, 2026

Starting around puberty, the limbic system becomes more sensitive to stimulus, which is one reason teenagers become both more emotional and more interested in having new and intense experiences.

From "The 57 Bus" by Dashka Slater

Related Words

• catalyst
• encouragement
• fillip
• impetus
• incentive
• motivation
• stimulant
• stimulation