irritate

v. annoy, bother, aggravate, anger; cause inflammation or extreme sensitivity (Medicine)

Irritation, in biology and physiology, is a state of inflammation or painful reaction to allergy or cell-lining damage. A stimulus or agent which induces the state of irritation is an irritant. Irritants are typically thought of as chemical agents (for example phenol and capsaicin) but mechanical, thermal (heat) and radiative stimuli (for example ultraviolet light or ionising radiations) can also cause irritation.
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v. irritate, provoke, vex, nettle, chafe, annoy, gall, rile, rouse, tease, enrage, anger, fret

adj. annoyed, angry, irritated, vexed, exasperated

v. irritate, anger, exasperate; excite

v. get irritated, be irritated

(v. t.)
To render null and void.
  

(v. t.)
To produce irritation in; to stimulate; to cause to contract. See Irritation, n., 2.
  

(v. t.)
To increase the action or violence of; to heighten excitement in; to intensify; to stimulate.
  

(v. t.)
To excite anger or displeasure in; to provoke; to tease; to exasperate; to annoy; to vex; as, the insolence of a tyrant irritates his subjects.
  

(n.)
To make morbidly excitable, or oversensitive; to fret; as, the skin is irritated by friction; to irritate a wound by a coarse bandage.
  

(a.)
Excited; heightened.