Synonyms of imperviable

1 Syllable
tight
2 Syllables
sealed
3 Syllables
immune, impervious, resistant, watertight, unmoved, hermetic
4 Syllables
impassive, unpierceable, impassable, impermeable, unaffected
5 Syllables
invulnerable, inaccessible, unapproachable, unreceptive, impenetrable