Refractometer

{
  "id": "MLC-T-MET-008480",
  "term": "Refractometer",
  "field": "Meteorology and atmospheric science",
  "definition": "An optical instrument that measures the refractive index of a substance, which is the ratio of the speed of light in a vacuum to its speed in the substance. In meteorology, refractometers are used to determine the density or composition of atmospheric gases, particularly water vapor. This measurement can provide insights into atmospheric conditions and the propagation of electromagnetic waves.",
  "url": "https://mlchart.com/terminology/meteorology/refractometer/"
}