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

Stars are arranged by spectral class; from hot to cool, the classes are O, B, A, F, G, K, M, L, T, and Y. — Encyclopedia Britannica, 14 Aug. 2026

Essentially a portable acoustic expert, SensorMAX continuously processes spectral energy profiles and data from up to eight subsurface sonobuoys simultaneously – doubling the feed capacity of legacy systems. — David Szondy august 12, New Atlas, 13 Aug. 2026

The team computed 500 spectral points across the observed wavelength band, applying the transmission profile of the real interference filter and blurring the result to match the real telescope’s resolution. — Jacek Krywko, ArsTechnica, 7 Aug. 2026

As this unfolds, La’An attempts to work the ship’s computer but only finds more footage of Harper, who then shows up in person in desiccated, spectral form before disappearing. — Keith Phipps, Vulture, 30 July 2026

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