Meaning of superglacial

su•per•gla•cial

Pronunciation: (s"pur-glā'shul), [key]
— adj.
  1. on the surface of a glacier.
  2. believed to have been formerly on the surface of a glacier: superglacial debris.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.