Synonyms of impregnable in English:

impregnable


See definition of impregnable

adjective

1‘such a castle must have been impregnable’

SYNONYMS

invulnerable, impenetrable, unattackable, unassailable, inviolable, secure, strong, stout, safe, well fortified, well defended

invincible, unconquerable, unbeatable, indestructible

ANTONYMS

vulnerable

2‘an impregnable parliamentary majority’

SYNONYMS

unassailable, unbeatable, undefeatable, unshakeable, invincible, indomitable, unconquerable, unstoppable, invulnerable

ANTONYMS

vulnerable

3‘as a working theory, this is impregnable’

SYNONYMS

irrefutable, incontrovertible, undeniable, indisputable, incontestable, unquestionable, unassailable, beyond question, beyond doubt, indubitable

flawless, faultless, watertight, airtight, foolproof, without loopholes

ANTONYMS

flawed