adjectives
(of persons or their actions) able or disposed to inflict pain or suffering
"a barbarous crime"; "brutal beatings"; "cruel tortures"; "Stalin's roughshod treatment of the kulaks"; "a savage slap"; "vicious kicks"
wild and menacing
"a pack of feral dogs"
without civilizing influences
"barbarian invaders"; "barbaric practices"; "a savage people"; "fighting is crude and uncivilized especially if the weapons are efficient"-Margaret Meade; "wild tribes"
marked by extreme and violent energy
"a ferocious beating"; "fierce fighting"; "a furious battle"