aeronaut vs airman

aeronaut and airman both are nouns.

Word	Noun	Adjective	Verb	Adverb
aeronaut	Yes	No	No	No
airman	Yes	No	No	No

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

Other hyponyms of aeronaut include airwoman, aviatress, aviatrix, airplane pilot, pilot.

aeronaut (noun)	airman (noun)
someone who operates an aircraft	a male who operates an aircraft