The infrared region of the electromagnetic spectrum; electromagnetic wave frequencies below the visible range:
— They could sense radiation in the infrared.

synonym: infrared frequency.

Electromagnetic radiation with wavelengths longer than visible light but shorter than radio waves.

synonyms: infrared emission, infrared light, infrared radiation.

Dutch: infraroodstraling
Polish: promieniowanie infraczerwone, podczerwień, promieniowanie nadczerwone

Having or employing wavelengths longer than light but shorter than radio waves; lying outside the visible spectrum at its red end.

Polish: podczerwony