(spectra, or spectrums)
1.
The spectrum is the range of different colours which is produced when light passes through a glass prism or through a drop of water. A rainbow shows the colours in the spectrum.
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2.
A spectrum is a range of a particular type of thing.
Politicians across the political spectrum have denounced the act...
The term 'special needs' covers a wide spectrum of problems.
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3.
A spectrum is a range of light waves or radio waves within particular frequencies.
Vast amounts of energy, from X-rays right through the spectrum down to radio waves, are escaping into space...
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