abyss

n. 深渊，深坑

abstract noun, abstracted, abstractedly, abstraction, abstruse, abstrusely, abstruseness, absurd, absurdity, absurdly, abundance, abundant, abundantly, abuse, abusive, abusively, abut, abutment, abysmal, abysmally, AC (also ac), acacia, academic, academically, academically biased, academician, academy, ACAS, accede, accelerando, accelerate, acceleration, accelerator, accent, accentuate, accentuation, accept, acceptability, acceptable, acceptably,