Meaning of mesopelagic

mes•o•pe•lag•ic

Pronunciation: (mez"u-pu-laj'ik, mes"-, mē"zu-, -su-), [key]
— adj. Oceanog.
  1. of, pertaining to, or living in the ocean at a depth of between 600 ft. (180 m) and 3000 ft. (900 m).
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.