|a stew of meat, vegetables, potatoes, etc.|
|an extraordinary or unusual thing, person, or event; an exceptional example or instance.|
|actinometer (āk'tə-nŏm'ĭ-tər) Pronunciation Key
Any of several instruments used to measure radiation, such as a pyrheliometer.
in chemistry, a substance or a mixture of substances that reacts through the action of light and that, because of the easily determined quantitative relationship between the extent of the reaction and the energy of the absorbed light, is used as a standard for measurement of light energies involved in photochemical work
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