IRRITATION
Ir`ri*ta"tion, n. Etym: [L. irritatio: cf. F. irritation.]
1. The act of irritating, or exciting, or the state of being irritated; excitement; stimulation, usually of an undue and uncomfortable kind; especially, excitement of anger or passion; provocation; annoyance; anger. The whole body of the arts and sciences composes one vast machinery for the irritation and development of the human intellect. De Quincey.
2. (Physiol.)
Defn: The act of exciting, or the condition of being excited to action, by stimulation; — as, the condition of an organ of sense, when its nerve is affected by some external body; esp., the act of exciting muscle fibers to contraction, by artificial stimulation; as, the irritation of a motor nerve by electricity; also, the condition of a muscle and nerve, under such stimulation.
3. (Med.)
Defn: A condition of morbid excitability or oversensitiveness of an organ or part of the body; a state in which the application of ordinary stimuli produces pain or excessive or vitiated action.
IRRITATIVE
Ir"ri*ta*tive, a.
1. Serving to excite or irritate; irritating; as, an irritative agent.
2. Accompanied with, or produced by, increased action or irritation; as, an irritative fever. E. Darwin.
IRRITATORY
Ir"ri*ta*to*ry, a.