spectrum.

1. A range of electromagnetic frequencies or wavelengths, often displayed by intensity.

2. A range extending between contrasting positions, qualities, or types.

Use it for

Words that belong together

• visible spectrum
• emission spectrum

On the page

The instrument recorded an unexpected line in the emission spectrum.

Usage notes

Primary category: academic / formal. Forms: Singular spectrum; plural spectra or spectrums. Legacy lexical fields mirror sense 1 only. Use numbered sense fields for all meanings. Established modern English lexical item. No separate regional spelling or grammatical inflection entry. Writing functions: analysis, explanation. Commonness: moderately common.