n.

1. 深渊；深坑；深处[C]
   One slip on this mountain and you will fall into the abyss.

   在这座山上一失足便会跌入万丈深渊。

2. 任何深不可测的事物；（智力等的）深邃[C][U]
   abyss of shame

   羞愧无比

3. 【宗】（创世之前的）混沌

n.

1. a very deep chasm.
2. (the abyss) a catastrophic situation seen as likely to occur.