adj. 25B6; adjective MERCILESS, pitiless, cruel, heartless, hard-hearted, cold-hearted, cold-blooded, harsh, callous, unmerciful, unforgiving, uncaring, unsympathetic, uncharitable; remorseless, unbending, inflexible, implacable; brutal, inhuman, inhumane, barbarous, barbaric, savage, sadistic, vicious.
merciful.