sez that:* Saturn has 62 moons with confirmed orbits, 53 of which have names and only 13 of which have diameters larger than 50 kilometers*
but later talks about "moonlets.
But Aegaeon is tiny, hardly larger than the largest “moonlet”.
Have they defined what is a moon vs a “moonlet”?
Wiki Moonlet - Wikipedia sez amongst other things that moons embedded in ring systems are called moonlets. As are moons of moons and moons of asteroids. It seems the Saturnian stuff fits the first definition.
I have no clue what IAU says on the topic. The wiki article’s cites were to examples of usage, not to an official glossary.
The IAU has not defined moonlet or moon and they aren’t going to any time soon. Probably never will. Use the terms however you want.