Zymometer

noun

2. An instrument for ascertaining the degree of fermentation of a fermenting liquor. Also zymosimeter.
3. An instrument for ascertaining the degree of fermentation occasioned by the mixture of different liquids, and the degree of heat which they acquire in fermentation.
4. An instrument for ascertaining the degree of fermentation occasioned by the mixture of different liquids, and the degree of heat which they acquire in fermentation; a zymosimeter.