Synonyms and related words :
abortive, beyond reach, bootless, closed forever to, closed to, fruitless, impenetrable, impervious, inaccessible, ineffective, ineffectual, lost to, out of reach, un-come-at-able, unaccessible, unapproachable, unattainable, unavailing, undiscoverable, ungettable, unobtainable, unprocurable, unproductive, unreachable, unsecurable, useless, vain