irradiance
noun
ir·ra·di·ance
i-ˈrā-dē-ən(t)s 
1
2
: the density of radiation incident on a given surface usually expressed in watts per square centimeter or square meter
Examples of irradiance in a Sentence
Recent Examples on the Web
There is no standardized regulatory framework requiring consumer LED devices to verify or publish their irradiance.
—
Jesse Pines, Forbes.com, 28 May 2026
Researchers at the Pontifical Catholic University of Chile studied CEEs in solar panels and published a paper in 2019, highlighting the impact of cloud irradiance on solar power plants.
—Ameya Paleja, Interesting Engineering, 25 May 2026
Researchers isolated phenomena including the El Niño weather phase, volcanic eruptions and solar irradiance.
—Los Angeles Times, 9 Mar. 2026
Red light device manufacturer Bon Charge co-founder, Katie Mant, notes that the most relevant factor is irradiance, which is the dose of light delivered per square centimeter.
—Emily Peck, Wired News, 12 Dec. 2025
Solar power works for missions close to the sun, but by the time a spacecraft gets to Jupiter, the available solar irradiance drops below 4 percent of that on Earth.
—IEEE Spectrum, 25 Aug. 2025
Examples are automatically compiled from online sources to
show current usage.
Read More
Opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
Send us feedback.
Jesse Pines, Forbes.com, 28 May 2026
Researchers at the Pontifical Catholic University of Chile studied CEEs in solar panels and published a paper in 2019, highlighting the impact of cloud irradiance on solar power plants.
—Ameya Paleja, Interesting Engineering, 25 May 2026
Researchers isolated phenomena including the El Niño weather phase, volcanic eruptions and solar irradiance.
—Los Angeles Times, 9 Mar. 2026
Red light device manufacturer Bon Charge co-founder, Katie Mant, notes that the most relevant factor is irradiance, which is the dose of light delivered per square centimeter.
—Emily Peck, Wired News, 12 Dec. 2025
Solar power works for missions close to the sun, but by the time a spacecraft gets to Jupiter, the available solar irradiance drops below 4 percent of that on Earth.
—IEEE Spectrum, 25 Aug. 2025
Cite this Entry
“Irradiance.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/irradiance. Accessed 30 May. 2026.
Copy CitationMedical Definition
irradiance
noun
ir·ra·di·ance
ir-ˈād-ē-ən(t)s
: the density of radiation incident on a given surface usually expressed in watts per square centimeter or square meter
Love words? Need even more definitions?
Merriam-Webster unabridged
