Intransmutable

a.

1.

Not capable of being transmuted or changed into another substance.

changeless, constant, immutable, incommutable, inconvertible, indefeasible, inert, insusceptible of change, invariable, irretrievable, irreversible, irrevocable, lasting, noble, nonreturnable, nonreversible, permanent, reverseless, unalterable, unalterative, unaltered, unchangeable, unchanged, unchanging, undeflectable, undeviating, unmodifiable, unremitting, unrestorable, unreturnable, unsusceptible, unvariable, unvarying