earplug

1. Luckily we took earplug with us, as the traffic outside our room was very noisy.
   真幸运，我们带有耳塞，因为房间外面的车辆噪音太大。

ear.plug

n.（名词）
An object made of a soft, pliable material, such as cotton or rubber, and fitted into the ear canal to block the entry of water or sound.
耳塞：一种由柔软而灵便的材料制成的东西，如棉、橡胶等材料，以嵌入耳道挡住水或声音的进入
An earphone, especially one that fits into the ear.
耳塞：耳机，尤指塞入耳中的那一种