1. An image of something seen, continuing after the eyes are closed; the colours formed on a screen in a darkened chamber by the resolution of light from a luminous body through means of a prism or otherwise.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• spectram,
• spectum,
• spectrul,
• specrtum,
• spectrom,
• spetrium,
• specturm,
• spectrem,
• spectrun,
• sectrum,
• spectrual,
• spectirum,
• specktrum,
• spectr,
• sepectrum,
• sprectrum,
• spectrium,
• spectrim,
• spetrum,
• spectruim

• spectrogram,
• spectate,
• spice tree,
• full-spectrum,
• spectator,
• absorption-spectrum,
• autism-spectrum,
• SPECTROM,
• radio-spectrum,
• spectre,
• cross-spectrum,
• spectrem,
• spektrum,
• spectral,
• spector,
• spectacular,
• fortification-spectrum,
• specter,
• spicate,
• spread-spectrum,
• Specht,
• narrow-spectrum,
• broad-spectrum.

The adjective form of the word "spectrum" is "spectral".

The plural of the "spectrum" can be the "spectrums".

The singular of the "spectrum" can be the "spectrum".