irritant
/ˈɪrɪtənt; `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. irritant, 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.