cavern

/ˈkævərn/
noun
  1. A large, deep underground cave or hollow space in rock, often formed by natural processes.
    • The bats roosted in the dark recesses of the limestone cavern.
    • The explorers discovered a vast cavern filled with ancient stalactites.
    • We hiked deep into the mountain and found a hidden cavern behind the waterfall.
verb
  1. To hollow out or form a cavern-like space; to erode or dig out a large cavity.
    • Water dripping through the ceiling slowly cavered the limestone into a wide opening.
    • The miners cavered a large chamber to store their equipment.
    • Over millions of years, the river cavered the soft rock beneath the plateau.
What does "cavern" mean? | whatsthatwordmean | whatsthatwordmean