abyssal hill

noun

: any of the numerous relatively low elevations arising from the ocean floor

Low abyssal hills (less than 1 kilometer above the surrounding ocean bottom) cover about 80% of the Pacific floor and about half of the Atlantic.

—M. Grant Gross, Oceanography 5th Edition, 1990

compare abyssal plain, seamount

Word History

First Known Use

1960, in the meaning defined above

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