unpierceable
Resists all penetration
Unable to be pierced or penetrated.
The word describes materials or surfaces too hard, thick, or resilient for anything to pass through: The knight's unpierceable armor deflected every blow.
Figuratively, it can describe emotional defenses: She maintained an unpierceable composure throughout the interrogation.
Impossible to pass through
- invulnerableImmune to all harm
- imperviousUnable to be affected
- bulletproofResistant to gunfire
- chainmailArmor of linked rings
plate armor · kevlar · mail · cuirass · breastplate · hauberk · scale armor · lamellar
Utterly impervious, unshakeable
- diamondCrystallized carbon gemstone
- tungstenElement seventy-four
- titaniumElement twenty-two
- hardened steelHeat-treated ferrous alloy
carbon fiber · ceramic plate · reinforced · tempered · hardened · indestructible · unbreakable · solid
Incapable of being defeated
- unassailableImpossible to attack successfully
- indomitableCannot be overcome
- unyieldingRefusing to give way
- steadfastFirmly loyal, unshakeable
resolute · unwavering · impervious · immune · resistant · unshakable · ironclad · airtight
Transformed into cipher
- firewallNetwork access control system
- secureProtected from harm
- protectedKept from harm
- unhackableImpossible to breach digitally
tamper-proof · authenticated · verified · locked · sealed · safeguarded · shielded · cybersecurity
impenetrable
Impossible to pass through
- invulnerableImmune to all harm
- imperviousUnable to be affected
- bulletproofResistant to gunfire
chainmail · plate armor · kevlar · mail · cuirass · breastplate · hauberk · scale armor · lamellar · brigandine
adamantine
Utterly impervious, unshakeable
hardened steel · carbon fiber · ceramic plate · reinforced · tempered · hardened · indestructible · unbreakable · solid · dense
invincible
Incapable of being defeated
- unassailableImpossible to attack successfully
- indomitableCannot be overcome
- unyieldingRefusing to give way
steadfast · resolute · unwavering · impervious · immune · resistant · unshakable · ironclad · airtight · watertight
encrypted
Transformed into cipher
unhackable · tamper-proof · authenticated · verified · locked · sealed · safeguarded · shielded · cybersecurity · encryption
fortress
Heavily defended military structure
- bunkerReinforced subterranean stronghold
- vaultSecure storage chamber
- strongholdFortified place of defense
citadel · bastion · bulwark · rampart · fortification · wall · blockade · barricade · membrane · seal
unpierceablepierceable
Capable of being punctured
penetrable · permeable · porous · puncturable · breachable
unpierceablevulnerable
Open to attack
defenseless · exposed · unprotected · fragile · susceptible
piercing, pierce, pierced, pierces, piercingly, piercings, piercer, unpierced, piercers