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.

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actinometer British  

/ ˌæktɪnəʊˈmɛtrɪk, ˌæktɪˈnɒmɪtə /

noun

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

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actinometer Scientific  

/ ăk′tə-nŏm′ĭ-tər /

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

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Other Word Forms

• actinometric adjective
• actinometrical adjective
• actinometry noun

Etymology

Origin of actinometer

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

Example Sentences

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

From Photogravure by Blaney, Henry R.

Another object was, to bring down specimens of air from different altitudes, for analysis; to try the effect of the actinometer at great elevations; and to note the hygrometric condition.

From Chambers's Edinburgh Journal, No. 456 Volume 18, New Series, September 25, 1852 by Chambers, Robert

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

The actinometer of M. Violle is, in principle, a sphere of copper, blackened externally, and having inside a thermometric apparatus which registers some distance away.

From Sounding the Ocean of Air by Rotch, A. Lawrence

The actinometer consists of a large cylindrical thermometer bulb, with a scale considerably lengthened, so that minute changes may be easily seen.

From A Treatise on Meteorological Instruments Explanatory of Their Scientific Principles, Method of Construction, and Practical Utility by Negretti, Henry