Kenneth G. Wilson (1923–). The Columbia Guide to Standard American English. 1993.
abysm, abyss (nn.)
These are two old synonyms for “the pit,” the fearsome void that medieval and later Christians envisioned below the earth. We now use abyss fairly frequently, meaning either “hell” or “any great hole,” such as the seemingly bottomless cracks in the ice that Antarctic explorers had to avoid. Abysm (from which the adjective abysmal comes) is much less common these days and seems to be reserved almost wholly for a figurative sense dealing with time.
