impervious – 1. not allowing liquid to go through 2. unable to be affected by

(Pronounced im-puh-vee-uhs)

To remember the definition of the word impervious, use the following mnemonic:

The roof had no imperfections and it was obvious (impervious) that it was not letting any water through. He was not affected by whatever happens with the weather. 

Examples of impervious in a sentence (1. not allowing liquid to go through)

His supposedly impervious boots were now filled with water. 

While the impervious tent did keep them dry, it didn't keep them very warm. 

The roof was far from impervious and would leak every time it rained. 

Examples of impervious in a sentence (2. unable to be affected by)

She seemed completely impervious to the cold. 

With his new armour he was impervious to their attacks. 

The car was built like a tank and impervious to small arms fire.