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hydrospace

[hahy-druh-speys]
noun
  1. the regions beneath the surface of the oceans and seas.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
hydrospace in Science

hydrospace

[hī′drə-spās′]
  1. The regions beneath the ocean's surface, especially when considered as an area to be studied, as in marine mammal research or sonar mapping of the ocean floor.
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