WordNet sense 1 (a small valley between mountains):

holler

WordNet sense 2 (a depression hollowed out of solid matter):

hole

WordNet sense 3 (having nothing inside):

empty

WordNet sense 4 (having a sunken area):

sunken

WordNet sense 5 (being or suggesting a cavern):

cavernous

WordNet sense 6 (deliberately deceptive):

false

WordNet sense 7 (lacking sincerity):

insincere

WordNet sense 8 (having a tendency to reverberate or be repeatedly reflected):

ringing, reverberant

WordNet sense 9 (devoid of significance or point):

vacuous

WordNet sense 10 (having no meaning or direction or purpose):

nonmeaningful

WordNet sense 11 (remove the inner part or the core of):

dig, excavate

WordNet sense 12 (remove the interior of):

hollow out, core out