Sentence:  Numerous blocks of ice, to which the name "<WSD>serac</WSD>" is given, covered the plain. These are large fragments of frozen snow, almost rectangular. They take their name from the resemblance they bear to a compact cheese called "serac," which is made from skimmed milk, and pressed into rectangular cans. 
Meaning of the word marked with <WSD> tags:  A sharp tower of ice formed by intersecting crevasses of a glacier. (from mid 19th c.)