What is the structure formed of beams, girders, etc., with proper covering, which divides a building horizontally into stories. Floor in sense 1 is, then, the upper surface of floor in sense 2 called?

floor — The structure formed of beams, girders, etc., with proper covering, which divides a building horizontally into stories. Floor in sense 1 is, then, the upper surface of floor in sense 2. (Webster's 1913.)

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