The difference between Aviator and Flyer

Aviator as a noun:

An aircraft pilot. The use of the word may imply claims of superior airmanship, as in navy aviator vs. air force pilot.

Aviator as a noun (obsolete):

An experimenter in aviation.

Aviator as a noun (obsolete):

A flying machine.

Flyer as a noun:

A machine that flies.

Flyer as a noun:

Someone who pilots or rides in an airplane.

Flyer as a noun:

A leaflet, often for advertising.

Flyer as a noun:

The part of a spinning machine that twists the thread as it takes it to and winds it on the bobbin

Flyer as a noun (architecture):

An arch that connects a flying buttress into the structure it supports.

Flyer as a noun (acrobatics, cheerleading):

The person who is lifted and/or thrown by another person or persons.

Flyer as a noun (firearms):

A stray shot away from the group on a target.

Flyer as a noun:

A standard rectangular step of a staircase (as opposed to a winder).

Flyer as a noun:

A female kangaroo; a roo; a doe; a jill.

Flyer as a noun:

A leap or jump.

Flyer as a noun:

A risky investment or other venture.

Flyer as a verb (intransitive):

To distribute flyers (leaflets).

Flyer as a verb (transitive):

To distribute flyers in (a location) or to (recipients).