- relentless
- adj1. unyielding, unrelenting, implacable, unsparing; inexorable, remorseless, unflagging, dogged; undeviating, unswerving, persistent, persevering, undaunted; rigid, stern, strict, harsh, grim, austere; merciless, ruthless, unmerciful, pitiless, unpitying, unforgiving; unmitigable, inflexible, unbendable, resisting, grudging; hard, imperious, obdurate, adamant, adamantine, intransigent; uncompassionate, unfeeling, unsympathetic, intolerant.2. cruel, inclement, unkind; brutal, rigorous, fell, savage, ferocious; cold-blooded, marble-hearted, cold-hearted, stony-hearted; bloodthirsty, barbarous, ferine, inhuman, heartless, vicious, truculent, devilish.
A Note on the Style of the synonym finder. 2014.