"glaciation" in the noun sense
the condition of being covered with glaciers or masses of ice the result of glacial action
"Agassiz recognized marks of glaciation all over northern Europe"
the process of covering the earth with glaciers or masses of ice
Source: WordNet® (An amazing lexical database of English)
Princeton University "About WordNet®."
WordNet®. Princeton University. 2010.
View WordNet® License