photometer

noun

pho·​tom·​e·​ter fō-ˈtä-mə-tər How to pronounce photometer (audio)
: an instrument for measuring luminous intensity, luminous flux, illumination, or brightness

Examples of photometer in a Sentence

Recent Examples on the Web
These examples are automatically compiled from online sources to illustrate current usage. Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Past attempts with professional-grade hardware include a 1981 experiment that linked an electronic device called a photometer (think of it as a very fancy light meter) with a one-meter infrared telescope in Chile to successfully make daytime observations. Phil Plait, Scientific American, 26 July 2024 Euclid launched in July 2023 to probe the fine details of this sprawling structure with a state-of-the-art 600-megapixel visible-light camera and a wide-field near-infrared spectrometer and photometer. Stephanie Pappas, Scientific American, 8 Nov. 2023 Since then, ground controllers have carefully calibrated the observatory's two instruments—a 600-megapixel visible light camera and a 64-megapixel near-infrared spectrograph and photometer. Dan Goodin, Ars Technica, 8 Nov. 2023 The network, known as AERONET, contains more than 500 sun photometer instruments that measure global aerosol optical depth. Julia Musto, Fox News, 29 June 2023 The kit also includes a Bluetooth ColorQ photometer that gives you a digital readout of your test results. Nor'adila Hepburn, Better Homes & Gardens, 1 June 2023 People would come and discuss how to build a really precise photometer. Andrew Grant, Discover Magazine, 27 Nov. 2012 So Masson's group is now developing a portable spectral photometer to augment its plasmonic tongue, thereby ensuring accurate readings. Jennifer Ouellette, Ars Technica, 28 May 2020

Word History

Etymology

New Latin photometrum, from phot- + -metrum -meter

First Known Use

1779, in the meaning defined above

Time Traveler
The first known use of photometer was in 1779

Dictionary Entries Near photometer

Cite this Entry

“Photometer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/photometer. Accessed 16 Nov. 2024.

Medical Definition

photometer

1 of 2 noun
pho·​tom·​e·​ter fō-ˈtäm-ət-ər How to pronounce photometer (audio)
: an instrument for measuring the intensity of light, luminous flux, illumination or brightness by comparison of two unequal lights from different sources usually by reducing the illumination of one (as by varying the distance of the source or using a polarizing device) until the two lights appear equal with the amount of adjustment serving as the basis of comparison and the equality of illumination being judged by various means

photometer

2 of 2 transitive verb
: to examine with a photometer

More from Merriam-Webster on photometer

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!