Exact Match:
- implacable
- incapable of being placated; "an implacable enemy"
Synonyms:
- adamant,
- adamantine,
- avenging,
- cast-iron,
- cruel,
- dour,
- firm,
- flinty,
- grim,
- grudgeful,
- hard,
- hard-core,
- immovable,
- immutable,
- impliable,
- inelastic,
- inexorable,
- inflexible,
- intractable,
- intransigent,
- iron,
- irreconcilable,
- merciless,
- mortal,
- pitiless,
- punitive,
- punitory,
- rancorous,
- relentless,
- retaliatory,
- revanchist,
- revengeful,
- rigid,
- rigorous,
- rock-ribbed,
- ruthless,
- steely,
- stern,
- stiff,
- unaffected,
- unalterable,
- unappeasable,
- unbending,
- unchangeable,
- uncompassionate,
- uncompromising,
- unflinching,
- unforgiving,
- ungiving,
- unmoved,
- unrelenting,
- unsympathetic,
- unyielding,
- vengeful,
- vindicatory,
- vindictive