C2not thinking or worrying about any pain caused to others; cruel: ruthless ambitiona ruthless dictatorSome people believe that to succeed in this world you have to be ruthless.Unkind, cruel and unfeelingViolent or aggressiveTreating people or animals badlyInsults and abuseruthlessly
/-li/adverb›She ruthlessly pursued her ambition, letting nothing get in her way.Unkind, cruel and unfeelingViolent or aggressiveTreating people or animals badlyInsults and abuseruthlessness
/-nəs/noun[U]Unkind, cruel and unfeelingViolent or aggressiveTreating people or animals badlyInsults and abuse