IPA: /ˌkæv.ərˈnɪk.əl.əs/
KK: /kævərˈnɪkələs/
Describing organisms that live in caves or caverns.
Bats are cavernicolous creatures that thrive in dark, underground environments.
Cavernicolous → It is formed from "cavern" (from Latin "caverna", meaning cave) and "-icolous" (from Latin "-icolus", meaning dwelling or inhabiting). The word "cavernicolous" describes organisms that dwell in or inhabit caves.
Think of creatures that 'dwell' ('-icolous') in 'caves' ('cavern') — that's why cavernicolous refers to those that live in caves.