speleologist vs adventurer

speleologist and adventurer both are nouns.

Word	Noun	Adjective	Verb	Adverb
speleologist	Yes	No	No	No
adventurer	Yes	No	No	No

As nouns, adventurer is a hypernym of speleologist; that is, adventurer is a word with a broader meaning than speleologist:

speleologist: a person who explores caves
adventurer: someone who travels into little known regions (especially for some scientific purpose)

Other hypernyms of speleologist include explorer.

speleologist (noun)	adventurer (noun)
a person who explores caves	a person who enjoys taking risks
	someone who travels into little known regions (especially for some scientific purpose)