2. Very susceptible of anger or passion; easily inflamed or
exasperated; as, an irritable temper.
Vicious, old, and irritable.
Tennyson.
3. (Physiol.) Endowed with irritability; susceptible of irritation;
capable of being excited to action by the application of certain
stimuli.
4. (Med.) Susceptible of irritation; unduly sensitive to irritants or
stimuli. See Irritation, n., 3.
Syn. -- Excitable; irascible; touchy; fretful; peevish.
Ir"ri*ta*ble*ness, n. Irritability.
Ir"ri*ta*bly, adv. In an irritable manner.
Ir"ri*tan*cy (?), n. [From 1st Irritant.] (Scots Law) The state or
quality of being null and void; invalidity; forfeiture. Burrill.
Ir"ri*tan*cy, n. [From 2d Irritant.] The state or quality of being
irritant or irritating.
Ir"ri*tant (?), a. [LL. irritants, -antis, p. pr. of irritare to make
null, fr. L. irritus void; pref. ir- not + ratus established.] (Scots
Law) Rendering null and void; conditionally invalidating.
The states elected Harry, Duke of Anjou, for their king, with this
clause irritant; that, if he did violate any part of his oath, the
people should owe him no allegiance.
Hayward.
Ir"ri*tant, a. [L. irritans, -antis, p. pr. of irritare: cf. F.
irritant. See Irritate to excite.] Irritating; producing irritation or
inflammation.