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abyssopelagic zone

Scientific  
/ ə-bĭs′ə-pə-lăjĭk /
  1. A layer of the oceanic zone lying below the bathypelagic zone and above the hadopelagic zone, at depths generally between about 4,000 and 6,000 m (13,120–19,680 ft). The abyssopelagic zone ranges in temperature from 10° to 4°C (50° to 39°F).