1. The American seismologist who proposed a scale to measure the relative strength of earthquakes, which was introduced in 1935 and named after him. 2. A measure of the acidity or alkalinity of a solution. 3. The unit of sound intensity, named after the inventor of the telephone. 4. The name for the brightness of stars, either apparent or absolute.
Logarithmic scales (Richter, pH, Bel, Magnitude)