Physics.
any body that emits radiation at each wavelength in a constant ratio less than unity to that emitted by a black body at the same temperature.
Physics.
any body that emits radiation at each wavelength in a constant ratio less than unity to that emitted by a black body at the same temperature.
Random House Webster's Unabridged English dictionary. Полный английский словарь Вебстер - Random House . 2012