WordReference Random House Unabridged Dictionary of American English © 2026
sub•gla•cial
(sub glā′shəl),USA pronunciation adj.
sub•gla′cial•ly, adv.
- Geologybeneath a glacier:a subglacial stream.
- Geologyformerly beneath a glacier:a subglacial deposit.
- sub- + glacial 1810–20
'subglacial' also found in these entries (note: many are not synonyms or translations):