brute
bruːt
noun
a savagely violent person or animal.
he was a cold-blooded brute
savage,beast,monster,animal,sadist,barbarian,devil,demon,fiend,ogre,thug,lout,boor,oaf,ruffian,yahoo,rowdy,bully boy,swine,bastard,pig,radge
adjective
characterized by an absence of reasoning or intelligence.
a brute struggle for social superiority