Complex sentence: The term "tunturi" is a loan from Sámi, compare Kildin Sami "tūndâr", which means "uplands, treeless mountain tract", from which the word "tundra" is borrowed, as well.
Split into simpler sentences: The term "tunturi" is a loan from Sami, compare Kildin Sami "tūndâr", which means "uplands, treeless mountain tract". From this expression, the word "tundra" is borrowed, as well.