American Heritage® Dictionary of the English Language, Fourth Edition
- n. The intrinsic property in radiation that produces photochemical activity.
Century Dictionary and Cyclopedia
- n. The radiation of heat or light, or that branch of natural philosophy which treats of the radiation of heat and light.
- n. That property of light which, as may be seen in photography, produces chemical combinations and decompositions. A pencil of rays, when decomposed by refraction through a prism, is found to possess three properties, viz., the heating, the luminous, and the chemical or actinic. It was formerly supposed that the actinic property belonged peculiarly to the more refrangible part of the spectrum, beginning with the violet and extending far beyond the visible spectrum; it is now known, however, that the different rays differ essentially only in their wave-lengths, and that the phenomena of heat, light, or chemical action observed depend upon the surface on which the rays respectively fall. The violet end of the spectrum acts especially on the sensitive silver salts, but the chemical decomposition of the carbon dioxid (CO2) in the atmosphere involved in the growth of vegetation takes place most actively under the action of the yellow rays; and under proper conditions a photograph of even the ultra-red rays at the opposite end of the spectrum may be obtained on a gelatin plate sensitized with silver bromid.
- n. In botany, the chemical action of sunlight on plants.
- n. chemistry, physics That property of electromagnetic radiation that leads to the production of photochemical effects
GNU Webster's 1913
- n. The property of radiant energy (found chiefly in solar or electric light) by which chemical changes are produced, as in photography.
- n. the property of radiation that enables it to produce photochemical effects
- actin- + -ism (Wiktionary)
“Niépce, a Frenchman, discovered "actinism," that power in the sun's rays which produces a chemical effect; that granite rocks, and stone structures, and statues of metal, "are all alike destructively acted upon during the hours of sunshine, and, but for provisions of Nature no less wonderful, would soon perish under the delicate touch of the most subtile of the agencies of the universe.”
“Frenchman, discovered "actinism," that power in the sun's rays which produces a chemical effect; that granite rocks, and stone structures, and statues of metal "are all alike destructively acted upon during the hours of sunshine, and, but for provisions of”
“Light or luminous power to one portion; heat or calorific power to another; and chemical power or actinism to a third.”
“The mechanism must be sensitive, as such properties of matter as heat, light, electricity, magnetism, and actinism, are to be handled, caused to vanish and reappear, analyzed and measured.”
“Meanwhile, two or three interesting investigations naturally suggest themselves; to determine, for instance, the relative actinism of blue sky, haze, and clouds; also, the relative exposures proper to give at different hours of the day, at different seasons of the year, and in different countries.”
“Niépce, a Frenchman, discovered actinism, that power in the suns rays which produces a chemical effect; that granite rocks, and stone structures, and statues of metal, are all alike destructively acted upon during the hours of sunshine, and, but for provisions of Nature no less wonderful, would soon perish under the delicate touch of the most subtile of the agencies of the universe.”
“Considering the wondrous richness and variety of the terrestrial life wrought out by the few sunbeams which we catch in our career through space, we may well pause overwhelmed and stupefied at the thought of the incalculable possibilities of existence which are thrown away with the potent actinism that darts unceasingly into the unfathomed abysms of immensity.”
“Ericson, and even more from the influence of his sad holy doubt, a fresh touch of the actinism of the solar truth fell upon the living seed in her heart, and her life burst forth afresh, began to bud in new questions that needed answers, and new prayers that sought them.”
“It is the centre from which an inconceivable amount of force in the shape of light, heat, actinism, and probably other manifestations, is hourly poured forth.”
“_actinism_, are names of _effects of radiant energy_.”
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These come from gamma meditation ,I think.
"Luciferous Logolepsy is a collection of over 9,000 obscure English words. Though the definition of an 'English' word might seem to be straightforward, it is not. There exist so many adopted, deriv...
I enjoy collecting words, for I have no fear of them ever running out.
A list of words whose meanings I am learning, either because a) I don't know the meaning b) I know the meaning, but could stand to better appreciate certain inflections or secondary meanings or c) ...
I'm especially fond of ones written by Charles Sanders Peirce.
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