An ice age is a long period when much of the earth was frozen. The last ice age.
The last one ended about eleven thousand years ago and left Britain's whole landscape behind it. Strictly we are still in an ice age, since there is permanent ice at both poles.
1nounice ageA long period when much of the earth was frozen.
“The last ice age ended about eleven thousand years ago.”
ice age is a period.
A translation of German Eiszeit, coined in the nineteenth century when glaciers were first understood.
German
Eiszeit
English, today
ice age
Perhaps a German Eiszeit.
Etymology from Wiktionary, CC BY-SA
Practised in Dinosaurs & Prehistory