"Centigrade" and "Celsius" are terms that refer to the same temperature scale, but they have different historical origins. Here's the difference between them:

1. Centigrade:

   • The term "centigrade" was originally used to describe a temperature scale with 100 degrees between the freezing point and boiling point of water.
   • The centigrade scale was proposed by Swedish astronomer Anders Celsius in 1742, who defined the freezing point of water as 0 degrees and the boiling point of water as 100 degrees.
   • The centigrade scale was widely used until the mid-20th century.

2. Celsius:

   • The term "Celsius" is named after Swedish astronomer Anders Celsius, who proposed the centigrade temperature scale.
   • In 1948, the 9th General Conference on Weights and Measures adopted the name "Celsius" to honor Anders Celsius and to avoid confusion with other uses of the term "centigrade."
   • The Celsius scale retained the same temperature intervals as the centigrade scale, with the freezing point of water defined as 0 degrees and the boiling point of water defined as 100 degrees at standard atmospheric pressure.
   • Today, the Celsius scale is the standard temperature scale used in most countries around the world for scientific, meteorological, and everyday temperature measurements.

In summary, "centigrade" and "Celsius" both refer to the same temperature scale, but "Celsius" is the modern term used to describe the scale in honor of its inventor, Anders Celsius.