adventurer vs madcap

adventurer and madcap both are nouns.

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

As nouns, madcap is a hyponym of adventurer; that is, madcap is a word with a more specific, narrower meaning than adventurer:

adventurer (noun)	madcap (noun)
a person who enjoys taking risks	a reckless impetuous irresponsible person
someone who travels into little known regions (especially for some scientific purpose)

adventurer (adjective)	madcap (adjective)
	characterized by undue haste and lack of thought or deliberation