the entire spectrum, considered as a continuum, of all kinds of electric, magnetic, and visible radiation, from gamma rays having a wavelength of 0.001 angstrom to long waves having a wavelength of more than 1 million km.
[ 1935-40 ]
ELECTROMAGNETIC SPECTRUM
Meaning of ELECTROMAGNETIC SPECTRUM in English
Random House Webster's Unabridged English dictionary. Полный английский словарь Вебстер - Random House . 2012