stimulus

n. something which incites to action; something which quickens a physical or mental process

Stimulus may refer to:Stimulus (physiology), something external that influences an activityInput to a system in other fieldsIncentive
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Stimulus /stim·u·lus/ pl. stim´uli [L.] any agent, act, or influence which produces functional or trophic reaction in a receptor or an irritable [more]Stimulus - Community and Resources

Noun
1. any stimulating information or event; acts to arouse action
(synonym) stimulation, stimulant, input
(hypernym) information
(hyponym) evocation, induction, elicitation
(derivation) stimulate, excite, stir

n. stimulus, incentive, urge, stimulant, substance that quickens a vital process (Medicine)