a device for measuring intensity of radiation, especially that of the sun.


Nearby words

  1. actinoid,
  2. actinolite,
  3. actinology,
  4. actinomadura,
  5. actinomere,
  6. actinomorphic,
  7. actinomyces,
  8. actinomyces bovis,
  9. actinomyces israelii,
  10. actinomycetaceae

Compare actinograph.

Origin of actinometer

First recorded in 1825–35; actino- + -meter

Related formsac·tin·o·met·ric [ak-tin-oh-me-trik, ak-tuh-noh-] /ækˌtɪn oʊˈmɛ trɪk, ˌæk tə noʊ-/, ac·tin·o·met·ri·cal, adjectiveac·ti·nom·e·try, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for actinometer

British Dictionary definitions for actinometer



an instrument for measuring the intensity of radiation, esp of the sun's rays
Derived Formsactinometric (ˌæktɪnəʊˈmɛtrɪk) or actinometrical, adjectiveactinometry, noun

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Science definitions for actinometer



Any of several instruments used to measure radiation, such as a pyrheliometer.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.