Absolute Green Lantern: Abin, Ain, and the names that are really titles
The wording around Abin Sur makes a lot more sense once you stop reading every familiar term as somebody's first and last name.
In Absolute Green Lantern, Abin means the adept, the controller, the guardian. Sur is the green level of light. Put those together and an Abin Sur is a guardian at the green level. The comic eventually spells that out, but even before the explanation, he introduces himself as THE Abin Sur. That little word is doing some work.
Ain is different. An Ain is an initiate into the light. One of an Abin Sur's responsibilities is selecting those initiates. So when you see Ain Rao, Ain Sur, or Ain Aur, you're looking at an initiate associated with the red, green, or gold level. The second part tells you where they fit in the color system; the first tells you something about their role.
John calls himself Ain Aur after being selected for the gold flame. That doesn't mean every gold-associated person should automatically be called an Abin. The book is giving us distinct terms, and collapsing all of them into “a Lantern” loses the part it's trying to explain.
OA also gets expanded as Omega-Alpha. The early story connects it to judgment and the experience beyond the initial evaluation. I wouldn't reduce that to “it's the same Oa we already know, just with a different look.” These people are trying to translate something alien into terms they can understand.
And then there's Abin Qard, connected in the explanation to the Weaponers and the Blackstars. That uses the same vocabulary on the dark side of the argument. So you can start reading the terminology rather than just memorizing a list: Abin tells you guardian/controller, Ain tells you initiate, and Sur or Aur or Qard tells you which level is being discussed.
Absolute Green Lantern: Abin, Ain, and the names that are really titles
· Absolute Green Lantern