Plural of abyss; multiple bottomless pits, immeasurably deep chasms, or unfathomable voids.
Standard English pluralization of 'abyss' using the '-es' suffix (required because 'abyss' ends in a sibilant sound).
The ocean has actual abysses that are so deep that sunlight never reaches them—the deepest one, Challenger Deep, is nearly 7 miles down, deeper than Mount Everest is tall!
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