(noun) a depression hollowed out of solid matter

(noun) a small valley between mountains; "he built himself a cabin in a hollow high up in the Appalachians"

(noun) a cavity or space in something; "hunger had caused the hollows in their cheeks"

(verb) remove the interior of; "hollow out a tree trunk"

(verb) remove the inner part or the core of; "the mining company wants to excavate the hillsite"

(adjective satellite) devoid of significance or point; "empty promises"; "a hollow victory"; "vacuous comments"

(adjective satellite) as if echoing in a hollow space; "the hollow sound of footsteps in the empty ballroom"

(adjective satellite) deliberately deceptive; "hollow (or false) promises"; "false pretenses"

(adjective) 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"

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