What is "alcoholometer"

Alcoholometer \Al`co*hol*om"e*ter\, Alcoholmeter \Al`co*hol"me*ter\, n. [Alcohol + -meter.] (Chem.) An instrument for determining the strength of spirits, with a scale graduated so as to indicate the percentage of pure alcohol, either by weight or volume. It is usually a form of hydrometer with a special scale.

alt. A specialized form of hydrometer used to measure the amount of alcohol in a liquid (such as beer). n. A specialized form of hydrometer used to measure the amount of alcohol in a liquid (such as beer).