adjective

• Related to a metric temperature scale, originally defined as having the freezing point of water as 0 degrees and its boiling point as 100 degrees, at standard atmospheric pressure. The standardized definition has 0.01 °C as the triple point of water, and a difference in temperature of 1 °C corresponds to ¹⁄_(273.16) of the difference in temperature between the triple point and the absolute zero.
• Alternative letter-case form of Celsius [Related to a metric temperature scale, originally defined as having the freezing point of water as 0 degrees and its boiling point as 100 degrees, at standard atmospheric pressure. The standardized definition has 0.01 °C as the triple point of water, and a difference in temperature of 1 °C corresponds to ¹⁄_(273.16) of the difference in temperature between the triple point and the absolute zero.]