Impregnable /(?)/
Im·preg·na·ble
Impregnable
a.
-
Not to be stormed, or taken by assault; incapable of being subdued; able to resist attack; unconquerable; as, an impregnable fortress; impregnable virtue.
The man's affection remains wholly unconcerned and impregnable.
Impregnable
a.
- Capable of being impregnated, as the egg of an animal, or the ovule of a plant. (Biol.)