Speleologist

Tom is a speleologist.

Source: tatoeba (7969416)

In 1904 we had the pleasure of escorting that veteran speleologist, Monsieur E. A. Martel, through the old and the new caves at Wookey Hole.

Source: tatoeba (12123522)

Under this heading M. E. A. Martel, the distinguished speleologist or cave-explorer of Europe, whose researches have recently added considerably to our knowledge of the Adelsberg grotto, furnishes to La Nature an interesting account of the episode in the Lueg-Loch or Lur-Loch, near the Styrian capital, which so nearly resulted fatally to the seven members of the Höhlenforscher—Fasching, Fölzmann, Zweyer, Oswald, Maier, Kurz and Haidt—who, on the 28th of April, attempted the exploration of the lost passage of the Semriach.

Source: wiktionary

The first man known to have descended Gaping Gill is well known on the Continent as an expert cave-explorer or speleologist — to use the new term which he perhaps invented.

Source: wiktionary