hydrometer

n. instrument for measuring the specific gravity of liquids

A hydrometer is an instrument used for determining the specific gravity of liquids. It is usually made of glass and consists of a cylindrical stem and a bulb weighted with mercury or shot to make it float upright. The liquid is poured into a tall jar, and the hydrometer is gently lowered into the liquid until it floats freely.
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Noun
1. a measuring instrument for determining the specific gravity of a liquid or solid
(synonym) gravimeter
(hypernym) measuring instrument, measuring system, measuring device
(hyponym) salinometer

n. hydrometer, instrument for measuring the specific gravity of liquids

n. hydrometer, instrument for measuring the specific gravity of liquids