senseless in WordNet English dictionary

1. unresponsive to stimulation
   "he lay insensible where he had fallen"; "drugged and senseless"
   insensible  senseless 
   
2. not marked by the use of reason
   "mindless violence"; "reasonless hostility"; "a senseless act"
   mindless  reasonless  senseless 
   
3. (of especially persons) lacking sense or understanding or judgment
   nitwitted  senseless  soft-witted  witless 
   
4. serving no useful purpose; having no excuse for being
   "otiose lines in a play"; "advice is wasted words"; "a pointless remark"; "a life essentially purposeless"; "senseless violence"
   otiose  pointless  purposeless  senseless  superfluous  wasted