The property inherent in protoplasm of reacting to a stimulus. [L. irritabilitas, fr. irrito, pp. -atus, to excite]
- electric i. the response of a nerve or muscle to the passage of a current of electricity; in cases of degeneration in nerve or muscle this i. is altered or lost. See modal alteration, qualitative alteration, quantitative alteration.
- myotatic i. the ability of a muscle to contract in response to the stimulus produced by a sudden stretching.
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1) the property of protoplasm and of living organisms that permits them to react to stimuli
2 a) quick excitability to annoyance, impatience, or anger
b) abnormal or excessive excitability of an organ or part of the body (as the stomach or bladder)
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n.
(in physiology) the property of certain kinds of tissue that enables them to respond in a specific way to outside stimuli. Irritability is shown by nerve cells, which can generate and transmit electrical impulses when stimulated appropriately, and by muscle cells, which contract when stimulated by nerve impulses.
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ir·ri·ta·bil·i·ty (ir″ĭ-tə-bilґĭ-te) 1. the quality or state of being irritable. 2. abnormal responsiveness to slight stimuli.Medical dictionary. 2011.