1N-COUNT [usually singular]深渊 An abyss is a very deep hole in the ground. 深渊 [literary]
2N-COUNT [usually singular]险恶的境地 If someone is on the edge or brink of an abyss, they are about to enter into a very frightening or threatening situation. 险恶的境地 [literary]
He felt he was on the edge of an abyss; one false move and he was done for.
3N-COUNT [usually singular, with supplement]极大的差异;鸿沟 A very great difference between two people, things, or groups can be referred to as an abyss . 极大的差异;鸿沟 [literary]
How big is the abyss between what you think you are and what you actually are?