noun, plural: stimuli
(1) (physiology) A detectable change in the internal or external environment.
(2) (physiology) That which influences or causes a temporary increase of physiological activity or response in the whole organism or in any of its parts.
Any of the five senses will respond to a particular stimulus. Based on the stimuli applied to the sensory organs, there are two kinds of stimuli:
Word origin: From Latin stimulus (“‘goad, prick’”)