Noun
An instrument for determining the amount of polarization of light, or the proportion of polarized light, in a partially polarized ray.
Source: Webster's dictionaryThis usage makes a polarimeter a tool of great importance to those trading in or using sugar syrups in bulk. Source: Internet
This is measured using a polarimeter in which polarized light is passed through a tube of the liquid, at the end of which is another polarizer which is rotated in order to null the transmission of light through it. Source: Internet