Synonyms of the word 
IMPERMEABILITY → SOLIDITY - SOLIDNESS
impermeability
- n. the quality of being impermeable.
solidity
- n. The state or quality of being solid.
- n. Moral firmness; validity; truth; certainty.
- n. (geometry) The solid contents of a body; volume; amount of inclosed space.
solidness
- n. The state or quality of being solid.
If you are interested in words, visit the following sites :
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- 1word.ws/impermeability to play with words, suffixs, prefixs, etc.