/'ɪrɪtənt; `ɪrətənt/
adj causing irritation; irritating 有刺激性的; 刺激的
*a substance that is irritant to sensitive skins 对敏感的皮肤有刺激性的物质.

n
(a) substance that irritates, eg pepper in the nose 刺激物（如呛到鼻子里的胡椒）.
(b) (fig 比喻) thing that annoys 令人烦恼的事物
*The noise of traffic is a constant irritant to city dwellers. 车辆的噪音对城市居民是永无止境的骚扰.

n[C]
formal something that keeps annoying you over a period of time
　Low flying aircraft are a constant irritant in this area.
a substance that can make a part of your body painful and sore
　a skin irritant