Visible light

 is a Pre-Astro term that originally referred to the wavelengths that generate a response in a typical Terran Human eye (about 390 to 700 nm.) In terms of frequency, this corresponds to a band in the vicinity of 430–770 THz.

Most known Carbon-based life forms have visual receptors sensitive to at least a portion of the above range, and may also include sensitivity to infrared and/or ultraviolet.

The term is no longer commonly used.