actinometer

American  

[ak-tuh-nom-i-ter] / ˌæk təˈnɒm ɪ tər /

noun

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

---

actinometer British  

/ ˌæktɪnəʊˈmɛtrɪk, ˌæktɪˈnɒmɪtə /

noun

1. an instrument for measuring the intensity of radiation, esp of the sun's rays

---

actinometer Scientific  

/ ăk′tə-nŏm′ĭ-tər /

1. Any of several instruments used to measure radiation, such as a pyrheliometer.

---

Other Word Forms

• actinometry
  noun
• actinometric
  adjective
• actinometrical
  adjective

Etymology

Origin of actinometer

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

Example Sentences

The mystery was not a new type of infernal machine as they imagined but merely a home-made actinometer!

From Sixteen Months in Four German Prisons Wesel, Sennelager, Klingelputz, Ruhleben by Mahoney, Henry Charles

With daylight, however, the light is constantly fluctuating, and this renders the use of an actinometer a necessity for correct exposure.

From Wireless Transmission of Photographs Second Edition, Revised and Enlarged 1919 by Martin, Marcus J.

It should register about 40 deg. with an actinometer used to test silver solutions.

From Photogravure by Blaney, Henry R.

A Johnson's actinometer is very useful to time the exposure.

From Photogravure by Blaney, Henry R.

Then note down everything you have done—kind of view, stop, speed of plate, exposure of each plate, and length of exposure of actinometer.

From Scientific American Supplement, No. 492, June 6, 1885 by Various