Linked from
The 87 pages that link to Glacier, each with the reason it gives.
PermafrostCompared with: Permafrost is frozen ground; a glacier is surface ice that flows.
Sea iceCompared with: Glaciers form on land, unlike sea ice, which freezes directly from seawater.
RiverCompared with: A glacier is flowing water in solid form, not a liquid channel across land.
Ice shelfCompared with: A glacier is grounded ice; an ice shelf is its floating continuation.