unbreakable Synonyms

untransmutable unyielding unshakable undestroyable unavoided tough tight sturdy strong stony stiff steely stable unalterable steel-plated hardest uninjectable unexchangeable undecryptable undeciphered splinterless shatterproof rocklike rock hard nonbreaking nonbreakable reinforced long-lasting splinterproof solid impenetrable hardened hard flinty fixed firm everlasting eternal durable binding armored adamantine imperishable indestructible indissoluble rugged rocky rigid resistant lasting