Pronunciation: (glā'shul),[key] —adj. 1. of or pertaining to glaciers or ice sheets.
2. resulting from or associated with the action of ice or glaciers: glacial terrain. 3. characterized by the presence of ice in extensive masses or glaciers.
4. bitterly cold; icy: a glacial winter wind. 5. happening or moving extremely slowly: The work proceeded at a glacial pace. 6. icily unsympathetic or immovable: a glacial stare; glacial indifference. 7. Chem.of, pertaining to, or tending to develop into icelike crystals: glacial phosphoric acid.