risk taker vs adventurer

risk taker and adventurer both are nouns.

Word	Noun	Adjective	Verb	Adverb
risk taker	Yes	No	No	No
adventurer	Yes	No	No	No

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

risk taker: someone who risks loss or injury in the hope of gain or excitement
adventurer: a person who enjoys taking risks

Other hypernyms of risk taker include venturer.

risk taker (noun)	adventurer (noun)
someone who risks loss or injury in the hope of gain or excitement	a person who enjoys taking risks
	someone who travels into little known regions (especially for some scientific purpose)