Synonyms of the word 
RUTHLESS → MERCILESS - PITILESS - REMORSELESS - UNMERCIFUL - UNPITYING
ruthless
- adj. Without pity or compassion; cruel, pitiless.
merciless
- adj. Showing no mercy; cruel and pitiless.
pitiless
- adj. having, or showing, no pity; merciless.
- adj. having no kindly feelings; unkind.
remorseless
- adj. without remorse, mercy or pity.
- adj. unyielding or relentless.
unmerciful
- adj. not showing mercy.
unpitying
- adj. Not feeling or showing pity.
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