Speleologist is a word that refers to a person who studies caves and their natural formations. However, there are several other words that can be used as synonyms for speleologist. Some examples include cave explorer, cave scientist, cave specialist, and caver. These words each add a slight nuance to the meaning of speleologist. A cave explorer might be focusing more on the discovery aspect of caves, while a caver is more likely to be interested in caving as a hobby. Cave specialist might be someone who is highly experienced in studying the geological formations found in caves, while a cave scientist might be focused on the biological or environmental aspects of caves.