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1. Cause annoyance in; disturb, especially by minor irritations
   "It irritates me that she never closes the door after she leaves";
   - annoy, rag, get to, bother, get at [informal], rile, nark [Brit, slang], nettle, gravel [US], vex, chafe, devil, tick off [informal], roil [N. Amer]
    
2. Excite to an abnormal condition,, chafe or inflame
   "Aspirin irritates my stomach"
    
3. (physiology) excite to some characteristic action or condition, such as motion, contraction, or nervous impulse, by the application of a stimulus
   "irritate the glands of a leaf"

Derived forms: irritated, irritates, irritating

Type of: aggravate, displease, exacerbate, exasperate, excite, stimulate, worsen

Antonym: soothe

Encyclopedia: Irritate