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English definition of “spectrum”


noun [C] (COLORS)   /ˈspek·trəm/ (plural spectra  /ˈspek·trə/ or spectrums) physics
the set of colors into which a beam of light can be separated Spectrum also means a range of waves such as light waves or radio waves.
(Definition of spectrum noun (COLORS) from the Cambridge Academic Content Dictionary © Cambridge University Press)
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