The word "quartet" refers to a group of four people (though it also has meanings related to music), which is exactly the number of the sisters (yes, the Amazoness Quartet are said to be sisters), so that's where that part of their group name came from.
The "Amazoness" in the quartet's group name is a bit trickier, but that's partly because the Sailor Moon anime and manga differ in a number of things concerning said quartet. In the Sailor Moon anime, the 4 sisters were playing in the Amazon jungle or forest and this was where they discovered the mirror where Queen Nehelenia was.
Thus, the "Amazoness" in their name could be in reference to where they came from. However, there is also another thing that can be associated with the Amazoness Quartet and this would be the Amazons from Greek Mythology.
The Greek Amazons are a race or group made up only of women. These women are all warriors, and, as you can expect, they are all strong and powerful.
This is just like the Amazoness Quartet who may be young but are certainly not ones that should be trifled with.
The quartet can hold their own in a fight what with their abilities like being able to summon lemures or making use of their Amazon stones.
In Greek Mythology, the Amazons appear in a number of myths and stories. One of these is regarding one of the famous 12 Labors of Hercules or Heracles (he's a hero and demigod from Greek and Roman Mythology).
The labor in question is for Heracles to obtain the golden belt of the Amazon queen named Hippolyte. As the queen of the Amazons, Hippolyte could be associated with the eldest sister in the Amazoness Quartet since both of these ladies are the leaders of their respective groups.
Hera causes trouble by spreading rumors amongst the rest of the Amazons that Heracles is planning to carry off their queen. Of course, the Amazons weren't just going to stand by and let that happen, so they all donned their armor and prepared to fight Hercules.
A battle ensues, and, in the end, the Amazons lose and Heracles manages to get the golden belt that he came for. It was even said that Hippolyte had been killed alongside many other Amazons.
The fact remains, however, that the quartet were the antagonists or the villains in the show and thus, it was pretty much expected that they would end up losing to Sailor Moon and the rest of the protagonists, no matter how good the four girls may be.
Now, even though the Amazoness Quartet were initially only known as villains and followers of Queen Nehelenia, they ended up being redeemed in the Sailor Moon anime although that's pretty much all that we get.
However, in the Sailor Moon manga, we get considerably more than that regarding the quartet as we find out that they shouldn't have been the antagonists in the first place. This is because the four sisters are actually Sailor Senshi.
As Sailor Senshi, the four sisters are collectively known as the Sailor Quartet though they are sometimes referred to as the Asteroid Senshi. The reason for this is because the four girls that make up the quartet have actually been named after four asteroids.
So, what do you think of the Amazoness Quartet? They are an interesting bunch, aren't they? Don't you think it would have been nice if the Sailor Quartet could have made an appearance in the Sailor Moon anime too instead of being just limited to the manga?
*Notes:
- Image with added text was modified by Freya Yuki based on the image by dolldivine (CC:BY) from deviantArt
- Said image was chosen to represent or symbolize the Amazoness Quartet since there are exactly four figures in the photo and they are all different
- The rest of the pics are enlarged product images from Amazon.com; links shown above via Amazon's Native Shopping Ads widget
