ruth·less 
/ˈru:θləs/ adjective
/ˈru:θləs/ adjective [more ruthless; most ruthless] : having no pity : cruel or merciless
▪ a ruthless killer ▪ The journalist was ruthless in his criticism.
▪ a ruthless killer ▪ The journalist was ruthless in his criticism.
— ruth·less·ly adverb
▪ The slaves were ruthlessly abused by their owners.
▪ The slaves were ruthlessly abused by their owners.
— ruth·less·ness noun [noncount]
