ABYSSAL
abyssal
Adjective
- Belonging to, or resembling, an abyss; unfathomable. <ref name=SOED/>
- Of or belonging to the ocean depths, especially below 2000 metres (6500 ft): abyssal zone. <ref name=SOED/>
- Pertaining to or occurring at excessive depths in the earth's crust; plutonic. <ref name=SOED/>
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