here's some abstruse ones (and a joke):

firn [G] (also névé [F])
cirque [F] (also cwm [W])
randkluft [G]
rognon [F]
bergschrund [G]
moraine [F]

Then there was the guide who was explaining matters
to a group of tourists. "And these rock formations
were piled up by the glaciers," he said. " But where
are the glaciers?" asked an elderly woman. "They've
gone back, madam, to get some more rocks."