Nature
CAVERN
A cavern is a large underground chamber, typically part of a cave system formed by water dissolving rock. Over thousands of years, dripping mineral-rich water builds up stalactites and stalagmites. Some caverns host unique ecosystems adapted to total darkness.
CAVERN is the kind of word that shows up in themed word searches like Strands. Themed puzzles group words like this under a shared category — here, Nature.