hollow in WordNet English dictionary

1. remove the interior of
   "hollow out a tree trunk"
   hollow  hollow out  core out 
   
2. remove the inner part or the core of
   "the mining company wants to excavate the hillside"
   excavate  dig  hollow 
   

1. devoid of significance or point
   "empty promises"; "a hollow victory"; "vacuous comments"
   empty  hollow  vacuous 
   
2. not solid; having a space or gap or cavity
   "a hollow wall"; "a hollow tree"; "hollow cheeks"; "his face became gaunter and more hollow with each year"
   hollow 
   
3. as if echoing in a hollow space
   "the hollow sound of footsteps in the empty ballroom"
   hollow 
   

1. a depression hollowed out of solid matter
   hole  hollow 
   
2. a small valley between mountains
   "he built himself a cabin in a hollow high up in the Appalachians"
   hollow  holler 
   
3. a cavity or space in something
   "hunger had caused the hollows in their cheeks"
   hollow