stimulus

UK: /ˈstɪmjʊləs/ US: /ˈstɪmjələs/ ,(stim′yə ləs)

Inflections of 'stimulus' (n): npl: stimuli

WordReference Random House Learner's Dictionary of American English © 2025

stim•u•lus /ˈstɪmyələs/   n., pl. -li 

/-ˌlaɪ/ .
1. something that stimulates:
   [countable] Her economic plan calls for a two-part stimulus to the economy.
   [uncountable] Many of his economic advisers argued against a package of strong stimulus at this time.
   [countable] Fear or excitement is a stimulus to the adrenal gland to produce adrenalin.

WordReference Random House Unabridged Dictionary of American English © 2025

stim•u•lus  (stim′yə ləs), n., pl. -li 

(-lī′). 
1. something that incites to action or exertion or quickens action, feeling, thought, etc.:
   The approval of others is a potent stimulus.
2. Medicine, Physiology, Psychology, Drugs [Physiol., Med.] something that excites an organism or part to functional activity.

• Latin: a goad
• 1605–15

Synonyms

• 1. incitement, enticement, motive, provocation.
• 2. stimulant.

Antonyms

• 1. discouragement.

Collins Concise English Dictionary © HarperCollins Publishers::

stimulus / ˈstɪmjʊləs/ noun ( -li / -ˌlaɪ -ˌliː/)

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. a former name for stimulant

Etymology: 17th Century: from Latin: a cattle goad