astrogator vs navigator

astrogator and navigator both are nouns.

Word	Noun	Adjective	Verb	Adverb
astrogator	Yes	No	No	No
navigator	Yes	No	No	No

As nouns, navigator is a hypernym of astrogator; that is, navigator is a word with a broader meaning than astrogator:

astrogator: the navigator of a spacecraft
navigator: the member of an aircrew who is responsible for the aircraft's course

astrogator (noun)	navigator (noun)
the navigator of a spacecraft	in earlier times, a person who explored by ship
	the member of an aircrew who is responsible for the aircraft's course
	the ship's officer in charge of navigation