Celsius

UK: /ˈsɛlsɪəs/ US: /ˈsɛlsiəs/ ,(sel′sē əs, -shē-)

WordReference Random House Learner's Dictionary of American English © 2025

Cel•si•us /ˈsɛlsiəs/   adj. 

1. Physics of, relating to, or measured according to a temperature scale (ˈCel•si•us ˌscale) in which 0° represents the point at which ice forms, and 100° represents the point at which steam forms;
   Centigrade: [after a noun or number]
   It was 10 degrees Celsius, not bad for a winter's day.
   [before a noun]
   Our teacher told us to give the results in Celsius numbers.
   Compare Fahrenheit.

WordReference Random House Unabridged Dictionary of American English © 2025

Cel•si•us  (sel′sē əs, -shē-), adj. 

1. Physics Also, Centigrade. pertaining to or noting a temperature scale (Cel′sius scale′) in which 0° represents the ice point and 100° the steam point. Symbol: C  See illus. under thermometer. 
2. Thermodynamics of or pertaining 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. Symbol: C  Cf. Kelvin (def. 3).

• named after Anders Celsius (1701–44), Swedish astronomer who devised the scale

Collins Concise English Dictionary © HarperCollins Publishers::

Celsius / ˈsɛlsɪəs/ adjective

1. denoting a measurement on the Celsius scale
   Symbol: C

Etymology: 18th Century: named after Anders Celsius (1701–44), Swedish astronomer who invented it