Definition of ice ages:
(n) :
(sciences) A period of long-term reduction in the temperature of Earth's surface and atmosphere, resulting in the presence of major polar ice sheets that reach the ocean and calve icebergs.
(n) :
(colloquial) Any of several glacial periods (within a scientific ice age) marked by episodes of extensive glaciation alternating with episodes of relative warmth (interglacial).
(n) :
Alternative letter-case form of ice age. [(sciences) A period of long-term reduction in the temperature of Earth's surface and atmosphere, resulting in the presence of major polar ice sheets that reach the ocean and calve icebergs.]