As we all know, Sailor Moon features a number of lunar-based names. I’ve decided to compile a list of these names and their meanings.
Silver Millennium/Ginzuishou (Silver Crystal):
"Silver" is the color that is often used to describe the Moon; however, the color white is also used occasionally. This is because the color of the Moon ranges from anywhere from silver to white, and oftentimes a mixture of the two.
Usagi’s guardian cat is named Luna. The word “Luna” (and variants, such as “Lune”) itself means “Moon” in several languages (including as Latin, Spanish, and French). In addition, the root “Luna” is used as an adjective to describe the Moon; some words include “lunar,” “lunate,” “lunatic,” and “lunation.”
Minako’s guardian cat is named Artemis. He’s named after the Greek goddess Artemis, one of the most widely-venerated Ancient Greek deities; she was one of the Twelve Olympians and resided on Mount Olympus. Artemis was the goddess of the Moon, the hunt, archery, and maidenhood. Unlike Selene/Luna, Artemis was not the embodiment of the Moon; it was merely associated with her.
Although Artemis is a male cat, he is named after a goddess; this is because, in most cultures, the Moon is seen as feminine (as opposed to the masculine or neutral Sun) and has goddesses/female deities associated with it. Humorously, in the second chapter of Codename: Sailor V, Minako teases Artemis for having such a girly name.
The daughter of Luna and Artemis. Diana is named after the Italian goddess Diana, who was the goddess of the Moon, the hunt, wild animals, and birthing. Although Diana is equated with Artemis, she actually had an independent origin in Italy (although the two goddesses have much in common). Like Artemis, Diana was not an embodiment of the Moon but rather a deity associated with it.
The name “Serenity” seems to be a title passed down through the Moon Matriarchy; all three known members (Queen Serenity, Princess/Neo-Queen Serenity, and Small Lady Serenity) share this name. The name “Serenity” can have two separate meanings/origins, thanks to the “R” and “L” sounds being interchangeable in the Japanese language.
The first meaning, Serenity, can be interpreted in a couple of ways. The word “serenity” itself means “The state of being calm, peaceful, and untroubled.” The Serenities seen in Sailor Moon always have an air of grace and poise around them, and rule over kingdoms that are peaceful, content, and untroubled by war or famine. Also, in the manga, it was stated that the Moon Kingdom was located on Mare Serenitatis, or the Sea of Serenity. It’s possible that the Serenities took their name from Mare Serenitatis.
The second meaning, Selenity, comes from the Greek goddess and embodiment of the Moon, Selene. Selene fell in love with the mortal Endymion, which is where the names “Princess Serenity” and “Prince Endymion” come from. In both the anime and manga, Queen Serenity identifies herself as the being known as Selene (or Serene).