Main Entry: stim·u·lus

Pronunciation: \ˈstim-yə-ləs\

Function: noun

Inflected Form(s): plural stim·u·li \-ˌlī, -ˌlē\

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>