Many English speakers use the word "spelunking" to mean exploring caves.
Cave explorers themselves, however, usually  use the term "spelunkers"  in
reference to people who wander into caves without the proper training or
equipment. People who DO know what they are doing are called  cave
explorers.  Americans like to use "cavers" a lot.  "Potholers" is often used
by the British and everyone says "speleologists" if the people exploring the
caves are engaged in some sort of scientific work (as well as having fun).