Celsius temperature, Math - title, Math - title
Thermodynamic temperature minus Math - text, invariably expressed in the SI unit degree Celsius (Math - text) which is equal to the kelvin. Sometimes the misnomer centigrade temperature is used for Celsius temperature.
Source:
Green Book, p. 48
PAC, 1996, 68, 957 (Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)) on page 965