1. Deprived of life; no longer living
   "a lifeless body";
   - exanimate
    
2. Lacking animation, excitement or activity
   "it was a lifeless party until she arrived"
    
3. Destitute or having been emptied of life or living beings
   "after the dance the littered and lifeless ballroom echoed hollowly"
    
4. Not having the capacity to support life
   "a lifeless planet"

See also: dead, empty, unanimated

Encyclopedia: Lifeless