Synonyms for Inalienable (same or very similar meaning)
WordNet sense 1 (not subject to forfeiture):
unforfeitable
WordNet sense 2 (not liable to being annulled or voided or undone):
indefeasible
WordNet sense 3 (incapable of being transferred):
untransferable
WordNet sense 4 (incapable of being repudiated or transferred to another):
unalienable
From the ODE community, based on WordNet
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