grəˈviməd.ə(r), graˈv-, ˈgravəˌmēd.- noun
Etymology: French gravimètre, from gravi- + -mètre -meter
1. : a device similar to a hydrometer for determining the specific gravity of liquid or solid substances
2. : a sensitive weighing instrument that measures the variation in the gravitational field by detecting small differences in the weight of a constant mass at different points (as on the earth or sea)