Not to be persuaded or moved by entreaty or prayer; firm; determined; unyielding; unchangeable; inflexible; relentless; as, an inexorable prince or tyrant; an inexorable judge.(adjective)
source: webster1913
adjective satellite (s)
not to be placated or appeased or moved by entreaty(adj.all)
Example: Russia's final hour, it seemed, approached with inexorable certainty.