Spectral -

In technical contexts, "spectral" refers to the distribution of a signal's properties, like energy or power, across different frequencies.

The word is also a common adjective for things that are ghostly or immaterial. Spectral Content - an overview | ScienceDirect Topics Spectral

The ability of a sensor (like a camera) to distinguish between different wavelengths of light, such as infrared or ultraviolet, beyond what the human eye can see. In technical contexts, "spectral" refers to the distribution

The specific mix of wavelengths in a light source. This is used in astronomy to determine what stars are made of or how fast they are moving. The specific mix of wavelengths in a light source

In medicine, spectral features are used to analyze brain waves (EEG) for tasks like sleep staging. 2. Film and Fiction (The Ghostly)

This is the distribution of power over a frequency range, often described using Power Spectral Density (PSD) . It helps engineers see where the "strength" of a signal lies. Light and Imaging: