Celsius is, or relates to, the Celsius
temperature scale (previously known as the centigrade scale). The degree Celsius (symbol: °C) can refer to a specific temperature on the Celsius scale as well as serve as unit increment to indicate a temperature
interval (a difference between two temperatures or an
uncertainty). “Celsius” is named after the Swedish astronomer
Anders Celsius (1701 – 1744), who developed a similar temperature scale two years before his death.
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