Словарь синонимов английского языка - ruthless

(adj) pitiless, unpitying, cruel, unsympathetic, merciless, unmerciful, harsh, fierce, remorseless, uncompassionate, vicious, savage, ferocious, hard-hearted, callous, unfeeling, tough, severe, heartless, inhuman, brutal, brutish, unrelenting, relentless, Chiefly US and Canadian mean: The jail houses some of the country's most ruthless criminals. In all of history there was no more ruthless a tyrant.