Definition of "glacial"

He could remember a day that he had spent the whole of (he couldn't have been more than ten) running one of the great, creaking freight elevators at a glacial speed, answering the calls of the bell—one ring, five rings, three rings—with an almost unbearable sense of responsiblity.

1917, Everybody's Magazine - Volume 37, Issue 2, Ridgeway Company, page 56

I understand that you commented that the Japanese are moving at glacial speed. This is not the only area where they are moving at glacial speed. They are moving at glacial speed in terms of trade barriers, and it is one thing that the American people recognize.

1953, United States. Congress. House. Committee on Armed Services, Defense Department Authorization and Oversight, U.S. Government Printing Office, page 1251

Paradoxically, then, the electronic speed offered by computer-based decision-making is often overwhelmed by the glacial speed of data reformatting and checking.

1999, Michael Goodchild, Max J. Egenhofer, Robin Fegeas, Cliff Kottman, Interoperating Geographic Information Systems, Springer Science & Business Media, page 133

Progress on judicial reform has been glacial, meeting enormous resistance.

16 October 2010, “Under the volcano”, in The Economist

Lower-level people added front-line information that ordinarily wouldn't have made it up the hierarchy to the executive committee (or would have made it at glacial speed).

2014, John P. Kotter, Accelerate: Building Strategic Agility for a Faster-Moving World, Harvard Business Review Press, page 96

The Gulf States and Saudi Arabia are modernizing but at a glacial speed in a world moving at digital speed.

2014, Stuart E. Eizenstat, The Future of the Jews: How Global Forces are Impacting the Jewish People, Israel, and Its Relationship with the United States, Rowman & Littlefield, page 105