impermeable
adj. 不可渗透的，透不过的；不透气的；不透水的；不为所动的，沉着冷静的
例句
Sandstones generally make good aquifers, while finer-grained mudstones are typically impermeable.
砂岩通常是良好的含水层，而细粒泥岩通常是不透水的。
Beneath this active layer is a second layer called "permafrost", which is frozen all year around, and is impermeable to water.
在这一活跃层下面，是被称为“多年冻土”的第二层，终年冻结，不透水。
The canoe is made from an impermeable wood.
该独木舟用防水木材制成。
《柯林斯英汉双解大词典》
