Celsius

American  

[sel-see-uhs, -shee-] / ˈsɛl si əs, -ʃi- /

noun

1. Anders 1701–44, Swedish astronomer who devised the Celsius temperature scale.

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adjective

1. Also Centigrade pertaining to or noting a temperature scale Celsius scale in which 0° represents the ice point and 100° the steam point. C

2. Thermodynamics. of or relating to a temperature scale having the same units as the Celsius scale but in which the zero point has been shifted so that the triple point of water has the exact value 0.01°; Celsius temperatures are computed from Kelvin values by subtracting 273.15 from the latter. C

Celsius British  

/ ˈsɛlsɪəs /

adjective

1.  C.  denoting a measurement on the Celsius scale

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Celsius ¹ Scientific  

/ sĕl′sē-əs /

1. Relating to a temperature scale on which the freezing point of water is 0° and the boiling point of water is 100° under normal atmospheric pressure.

2. See Note at centigrade

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Celsius ² Scientific  

1. Swedish astronomer who invented the centigrade thermometer in 1742.

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Celsius ¹ Cultural  

1. A temperature scale, also called centigrade, according to which water freezes at zero degrees and boils at one hundred degrees.

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Celsius ² Cultural  

1. A temperature scale in which zero degrees is the freezing point of water and 100 degrees is the boiling point. Temperature in this scale is generally denoted by °C or, in scientific usage, C alone. (Compare Fahrenheit (see also Fahrenheit).)

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Etymology

Origin of Celsius

C18: named after Anders Celsius (1701–44), Swedish astronomer who invented it

Example Sentences

After more than 1,300 people died in 2024, when temperatures soared above 50 degrees Celsius, Saudi authorities introduced a range of heat-mitigation measures including more shaded areas and thousands of extra health workers.

From Barron's • May 22, 2026

However, computer models suggest that many areas could see maximum temperatures into the high-teens or low-twenties Celsius.

From BBC • May 13, 2026

The results show that average ocean temperatures have dropped by about 2 to 2.5 degrees Celsius over the past 3 million years.

From Science Daily • Apr. 24, 2026

That day, a Polymarket account with username “Hoaqin” made nearly $14,000 in profit by betting that Paris temperatures would peak at 21 degrees Celsius, Polymarket data shows.

From The Wall Street Journal • Apr. 23, 2026

“The average temperature of the world has gone up a little over one degree Celsius since the beginning of the industrial era in the 1800s,” Natalie told the crowd.

From "Two Degrees" by Alan Gratz