What does spectrum mean?

Question

can anyone tell me what spectrum means in a simplistic term

Answer 1

The spectrum is understood to mean that tiny part of all wave lengths that is classified as visible light: red, orange, yellow, green, blue, violet.

Answer 2

It really depends on the topic you use the word "spectrum".

In mass spectrometry, a mass spectrum is graph with ion (molecular gragments) masses versus intensity (or concentration).

In molecular physics, spectrum is a graph displaying the wavenumber (or the vibration's frequency, wich is equivalent, more or less, woth the wavenumber) versus intensity again.

And, as my previous answerer said, it can be a graph showing energy as a function of energy, in optics, for instance.

Answer 3

It is how energy is distributed as a function of frequency.  For instance, white light is really made up of light of all colors - the spectrum of teh white light shows you how much energy of each color light is present.