stimulus
stim·u·lus
noun \ˈstim-yə-ləs\plural ; stim·u·li \-ˌlī, -ˌlē\ (audio pronunciation) (audio pronunciation)
Definition of STIMULUS
1
: stimulant 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>
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