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manometer ma·nom·e·ter (mā-nŏm'ĭ-tər)
An instrument that is used for measuring the pressure of liquids and gases.
An instrument used to measure the pressure exerted by liquids and gases. Pressure is exerted on one end of a U-shaped tube partially filled with liquid; the liquid is displaced upwards on the other side of the tube by a distance proportional to the pressure difference on each side of the tube.