glaciation

noun3

1. •
   The process of covering with a glacier, or the state of being glaciated; the production of glacial phenomena; an ice age

   • This simulation aims at describing the hydrological conditions at a Swedish deep repository of nuclear waste during a glaciation. — 2006
2. •
   A particular instance of glacier formation.
3. •
   The act of freezing.

   • For cave glaciation to occur it is necessary that the air temperature outside the caves be negative either for all or part of a year; such conditions exist in many regions of the world. — 2017