Aneroid (&unr_;), a. [Gr. 'a priv. + nhros wet, moist + -oid: cf. F. anéroïde.] Containing no liquid; -- said of a kind of barometer.
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Aneroid barometer, a barometer the action of which depends on the varying pressure of the atmosphere upon the elastic top of a metallic box (shaped like a watch) from which the air has been exhausted. An index shows the variation of pressure.
[1913 Webster]