1. (

• grim ,
• inexorable ,
• relentless ,
• stern ,
• unappeasable ,
• unforgiving ,
• unrelenting

) not to be placated or appeased or moved by entreaty; "grim determination"; "grim necessity"; "Russia's final hour, it seemed, approached with inexorable certainty"; "relentless persecution"; "the stern demands of parenthood" ;

2. (

• adamant ,
• adamantine ,
• inexorable ,
• intransigent

) impervious to pleas, persuasion, requests, reason; "he is adamant in his refusal to change his mind"; "Cynthia was inexorable; she would have none of him"- W.Churchill; "an intransigent conservative opposed to every liberal tendency" ;