infrared

/ˌˈɪnfrəˌrɛd/

/ˈɪnfrərɛd/

Definitions of infrared

1. adjective

   having or employing wavelengths longer than light but shorter than radio waves; lying outside the visible spectrum at its red end
   “infrared radiation”

   “infrared photography”

   synonyms:

   invisible, unseeable

   impossible or nearly impossible to see; imperceptible by the eye
2. noun

   electromagnetic radiation with wavelengths longer than visible light but shorter than radio waves
   synonyms: infrared emission, infrared light, infrared radiation

   type of:

   actinic radiation, actinic ray

   electromagnetic radiation that can produce photochemical reactions
3. noun

   the infrared region of the electromagnetic spectrum; electromagnetic wave frequencies below the visible range
   “they could sense radiation in the infrared”

   synonyms: infrared frequency

   type of:

   frequence, frequency, oftenness

   the number of occurrences within a given time period