spectral

adjective

spec·​tral ˈspek-trəl 

1

: of, relating to, or suggesting a specter : ghostly

We felt a spectral presence in the old ballroom.

No ghost stood beside me, nor anything of spectral aspect; merely a motherly, dumpy little woman, in a large shawl, a wrapping-gown, and a clean, trim nightcap.

—Charlotte Brontë

2

: of, relating to, or made by a spectrum

especially : relating to or derived from the electromagnetic spectrum of visible light

Surfaces can differ in the proportion of incident light they reflect (dark ones reflect less than light ones) and in the spectral composition of the light they reflect.

—Principles Of Neural Science

Their examination supported the opinion that the stone was mined in India and cut in London. They also found that the spectral characteristics overlap those of known treated green diamonds.

—Lapidary Journal

spectrally

ˈspek-trə-lē 

adverb

Examples of spectral in a Sentence

Recent Examples on the Web

The mantis shrimp is nature’s high-speed boxer with multi-spectral vision, a creature that hits faster than a bullet’s acceleration and sees the unseen. —Kaif Shaikh, Interesting Engineering, 17 Oct. 2025

And the measurements of the scalar spectral index, plus the limits on primordial gravitational waves, favor certain models of inflation (like slow-roll, single-field models) while disfavoring others (like hybrid inflation and large-field models). —Big Think, 14 Oct. 2025

Scientists have long suspected that the will-o’-the-wisp’s spectral glow came from a chemical reaction in gases released by decaying organic matter. —Mindy Weisberger, CNN Money, 8 Oct. 2025

And in the Greenbrier Valley Theatre, a 19th century murder and spectral testimony remains one of Appalachia's most haunting legends. —Evie Carrick, Travel + Leisure, 7 Oct. 2025

Word History

First Known Use

1769, in the meaning defined at sense 1

Phrases Containing spectral

• spectral line

Rhymes for spectral

• multispectral

Kids Definition

spectral

adjective

spec·​tral ˈspek-trəl 

1

: of, relating to, or suggesting a specter : ghostly

2

: of, relating to, or made by a spectrum

Medical Definition

spectral

adjective

spec·​tral ˈspek-trəl 

: of, relating to, or made by a spectrum

spectrally adverb