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

Among the most famous is Julian Eltinge, a longtime patron and vaudeville star, who’s said to have made the occasional spectral appearance. —Alexandra Emanuelli, Southern Living, 26 Sep. 2025

Previous research has pursued a number of different ways to recover spectral details from conventional smartphone RGB camera data. —IEEE Spectrum, 23 Sep. 2025

In the video above, Geralt goes head-to-spectral-head with a wraith. —Kimberly Roots, TVLine, 13 Sep. 2025

One of the bottlenecks in frequency comb technology has been the high energy required for spectral broadening. —Neetika Walter, Interesting Engineering, 13 Sep. 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