What is any elevated object on land which serves as a guide to mariners; a beacon; a landmark visible from the sea, as a hill, a tree, a steeple, or the like. Shak called?

seamark — Any elevated object on land which serves as a guide to mariners; a beacon; a landmark visible from the sea, as a hill, a tree, a steeple, or the like. Shak. (Webster's 1913.)

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