actinometer

noun

ac·​ti·​nom·​e·​ter ˌak-tə-ˈnä-mə-tər How to pronounce actinometer (audio)
: any of various instruments for measuring the intensity of incident radiation
especially : one in which the intensity of radiation is measured by the speed of a photochemical reaction
actinometric adjective
actinometry noun

Example Sentences

Recent Examples on the Web More advanced systems can have all that, plus all or a selection of these: a rain gauge, an anemometer for measuring wind speed and direction, a barometer, and an actinometer for checking UV index and solar radiation. Adrienne Donica, Popular Mechanics, 4 Jan. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'actinometer.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

Etymology

actino- + -meter

First Known Use

1833, in the meaning defined above

Time Traveler
The first known use of actinometer was in 1833

Dictionary Entries Near actinometer

Cite this Entry

“Actinometer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/actinometer. Accessed 21 Mar. 2023.

Medical Definition

actinometer

noun
ac·​ti·​nom·​e·​ter ˌak-tə-ˈnäm-ət-ər How to pronounce actinometer (audio)
: any of various instruments for measuring the intensity of incident radiation
especially : one in which the intensity of radiation is measured by the speed of a photochemical reaction
actinometric adjective
actinometry noun
plural actinometries

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