The Collaborative International Dictionary
Areometer
Areometer \A`re*om"e*ter\ (?; 277), n. [Gr. 'araio`s thin, rare + -meter: cf. F. ar['e]om[`e]tre.] (Physics) An instrument for measuring the specific gravity of fluids; a form hydrometer.
Wiktionary
areometer
alt. Any device used to measure the specific gravity of liquids or the density of solids. n. Any device used to measure the specific gravity of liquids or the density of solids.