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erosion – n. the gradual destruction of something by natural forces
bay – n. a large area of water that is part of an ocean or lake and partly surrounded by land
navigation – n. the act, activity, or process of finding the way to get to a place when you are traveling in a ship, airplane, car
polar – adj. of or relating to the North or South Pole or the region around it
relocation – n. the act of moving something to
