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abyssal

American  
[uh-bis-uhl] / əˈbɪs əl /

adjective

  1. of or like an abyss; immeasurable; unfathomable.

  2. Oceanography. of or relating to the biogeographic zone of the ocean bottom between the bathyal and hadal zones: from depths of approximately 13,000 to 21,000 feet (4,000 to 6,500 meters).


abyssal British  
/ əˈbɪsəl /

adjective

  1. of or belonging to the ocean depths, esp below 2000 metres (6500 feet)

    abyssal zone

  2. geology another word for plutonic

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

abyssal Scientific  
/ ə-bĭsəl /
  1. Relating to the greatest depths of the oceans and to the organisms that live there. The abyssal zone encompasses all depths below 4,000 m (13,120 ft).

  2. Relating to the region of the ocean bottom between the bathyal and hadal zones, from depths of approximately 2,000 to 6,000 m (6,560 to 19,680 ft). The abyssal zone includes nearly two-thirds of the Earth's surface.


Etymology

Origin of abyssal

First recorded in 1600–10; from Medieval Latin abyssālis, abyss, -al 1

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

On the seafloor, you can find canyons, volcanoes and vast abyssal planes.

From Salon

Along with others in the mining industry, he disputes the environmental claims made and has argued that the abyssal zone - 3,000m to 6,000m below sea level - has very low concentrations of life.

From BBC

An underwater earthquake or a landslide can snap the cable deep in the abyssal zone.

From Los Angeles Times

At least 400 million years old, the family of lucinid clams inhabits a wide variety of habitats, from beautiful beaches to the dark abyssal depths.

From Science Daily

MBARI's Continental Margin Processes Team, led by Senior Scientist Charlie Paull, investigates how the morphology of the continental margin -- where the continental shelf transitions to the abyssal plain -- is sculpted and changed over time.

From Science Daily