1
[ adjective ] not to be placated or appeased or moved by entreaty

Examples

"grim determination" "grim necessity" "Russia's final hour, it seemed, approached with inexorable certainty" "relentless persecution" "the stern demands of parenthood

Related terms

implacable

2
[ adjective ] never-ceasing

Examples

"the relentless beat of the drums"

Related terms

continual

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