From AMS Glossary
The covering of a land area by glacier ice.
This term was coined by G. Taylor in the Antarctic and introduced by Wright and Priestly (1922) to distinguish the act of glacial inundation from its geologic consequences (glaciation). It is growing in use in Great Britain but still is considered unnecessary by some American geologists, who use "glacier covering."
Wright, Sir C. E., and Priestley, Sir R. E. 1922. Glaciology. British (Terra Nova) Antarctic Expedition 1910– 1913; Harrison and Sons Ltd, London, . 581 pp.