noun. The quality of being excitable; readiness or proneness to be provoked or moved into action; the quality of being easily agitated; nervousness.

noun. In physiology, irritability.

noun. The quality of being readily excited; proneness to be affected by exciting causes.

noun. The property manifested by living organisms, and the elements and tissues of which they are constituted, of responding to the action of stimulants; irritability.

noun. The state of being excitable

noun. A measure of how easy something is to excite

noun. excessive sensitivity of an organ or body part

noun. being easily excited

"From what has been said, it must be evident that life is the effect of a number of external powers, constantly acting on the body, through the medium of that property which we call excitability; that it cannot exist independent of the action of these stimuli; when they are withdrawn, though the excitability does not instantly vanish, there is no life, no motion, but the semblance of death."

reactivity  responsiveness  

depressants  erethism  excitation  fretfulness  impressibility  

irritability