flyer vs aviatrix

flyer and aviatrix both are nouns.

Word	Noun	Adjective	Verb	Adverb
flyer	Yes	No	No	No
aviatrix	Yes	No	No	No

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

Other hyponyms of flyer include airwoman, aviatress, airplane pilot, pilot, airman.

flyer (noun)	aviatrix (noun)
an advertisement (usually printed on a page or in a leaflet) intended for wide distribution	a woman aviator
someone who travels by air
someone who operates an aircraft