Ma-nŏm'e-ter, n.

n. [Gr. μανός, thin, rare, and μέτρον, measure; Fr. manomètre.] An instrument for measuring the tension or elastic force of gases, steam, &c., constructed usually on the principle of allowing the gas to exert its elastic force in raising a column of mercury in an open tube, or in compressing a portion of air or other gas in a closed tube, with mercury or other liquid intervening; or in bending a metallic or other spring so as to set in motion an index.