Definition of irritation : 1. 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. 2. 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. 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. mood, pain in the neck, rage, anger,
toughness, fervour, impatience, menace, rawness, annoying,
aggravator, bothering, peeve, drag, plague, nuisance,
excitement, pest, biliousness, fervor, choler, joke, concer