The Infinite Abyss is a characterization of what Khadgar saw when looking at the color of Sargeras' eyes during a vision — the battle between Aegwynn and the avatar of Sargeras. (LG 121)
This article or section includes speculation, observations or opinions possibly supported by lore or by Blizzard officials. It should not be taken as representing official lore.
It is possible that this is another name for the Twisting Nether.