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That side of a ship which is toward the wind, the windward side; a piece of plank placed in the ports of a ship when laid up in ordinary, and serving as a protection from bad weather: weather-boards are fixed in an inclined position, so as to turn off the rain without preventing the circulation of air: a board used in weather-boarding (which see).

To nail boards upon, as a roof or side of a house, lapping one over another, in order to prevent rain, snow, etc., from penetrating them.