Meaning : The infrared region of the electromagnetic spectrum. Electromagnetic wave frequencies below the visible range.
Example :
They could sense radiation in the infrared.
Synonyms : infrared frequency
Meaning : Electromagnetic radiation with wavelengths longer than visible light but shorter than radio waves.
Synonyms : infrared emission, infrared light, infrared radiation
Meaning : Having or employing wavelengths longer than light but shorter than radio waves. Lying outside the visible spectrum at its red end.
Example :
Infrared radiation.
Infrared photography.