Term: carbon dioxide laser (CO2 laser) https://doi.org/10.1351/goldbook.C00828 Definition: A continuous or pulsed source of coherent radiation normally tunable through the CO2 vibration–rotation band centred near 10.6 µm. Related Terms: 1) gas lasers (http://doi.org/10.1351/goldbook.G02585). 2) laser (http://doi.org/10.1351/goldbook.L03459). 3) coherent radiation (http://doi.org/10.1351/goldbook.C01130). Source: PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2233 (https://doi.org/10.1351/pac199668122223) Citation: 'carbon dioxide laser (CO<sub>2</sub> laser)' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.C00828 License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms. Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.