Desolate means barren. A place where the four grains do not grow is called desolate.
Abyss means deep. Water that emerges from the earth but does not flow is called an abyss.
To put it bluntly, the literal meaning of "Desolate Abyss" is a very, very deep pool of water in some godforsaken place. The water might even be a little smelly; after all, running water never goes stale, and an abyss is a body of stagnant water.
However, after Du Youqian's Flying Boat landed in the Desolate Abyss, he saw no pool of water. Instead, he saw a massive pit, so vast he couldn't see its edges and so deep it seemed bottomless.
Even with his eyesight and a Divine Sense that could probe nearly 2,300 zhang, he couldn't reach the bottom. It was truly profound.
Even if you couldn't fit the Himalayas in this pit, you could at least fit the Alps.
"Is the bottom of this pit filled with the corpses of the Demon Race?" Du Youqian asked, peering over the edge.
