Glaciers are large masses of ice that form over many years from compacted snow in areas where more snow falls than melts. They move slowly downhill due to their own weight.
Related terms
Icebergs: Large chunks of ice that break off from glaciers and float in the ocean.
Glacier Retreat: The shrinking or melting of glaciers over time due to climate change.
Moraine: Accumulations of rocks and debris carried by glaciers and deposited along their edges or at their terminus.