1 A badge or insignia consisting of stripes meeting at an angle, worn on the sleeve of a military or police uniform to indicate rank, merit, or length of service. 2  n. Heraldry A device shaped like an inverted V.  n.
In physiology, a stimulus (plural stimuli) is a detectable change in the internal or external environment. The ability of an organism or organ to respond to external stimuli is called sensitivity.When a stimulus is applied to a sensory receptor, it normally elicits or influences a reflex via stimulus transduction.ne internal stimulus that causes hormone release is blood pressure. Hypotension, or low blood pressure, is a large driving force for the release of vasopressin, a hormone which causes the retention of water in the kidneys.
Stimuli (usually) activate one or more of the senses. Stimuli can be internal as well as external. Internal stimuli signal the state of the body. Some examples of external stimuli: visual stimuli, like the screen in front of you; click of the keys; touch stimuli, like the feel of the keys under your fingertips. Some examples of internal stimuli: the feeling you describe as hunger, the churning sensation you experience when anxious or afraid.