D defs.my
Entry 1 sense Webster, 1913

Infrared Radiation

/ĭnˌ-frẽr-ĕd' rādˌ-ē-āsh'-ən/ · In·fra·red· Ra·di·a·tion · IPA
01 n. electromagnetic radiation having a wavelength of between 700 nanometers and 1 millimeter.
  1. 1.
    electromagnetic radiation having a wavelength of between 700 nanometers and 1 millimeter.(Physics)