Impregnable

Part of speech: adjective (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. South. -- Im*preg"na*ble*ness, n. -- Im*preg"na*bly, adv.

Part of speech: adjective (a.)

Capable of being impregnated, as the egg of an animal, or the ovule of a plant.