barbarous in WordNet English dictionary

1. (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"
   barbarous  brutal  cruel  fell  roughshod  savage  vicious 
   
2. primitive in customs and culture
   barbarous