ENGLISH
REFERENCE

infrared

n. · adj.
US //ˌɪnfɹɝˈɛd// UK //ˌɪnfɹəɹˈɛd// in·frared
  1. 1 invisible light/heat (n.)
    B2 Upper Intermediate Technical Science

    a type of light that you cannot see, but you can feel it as heat.

    electromagnetic radiation with wavelengths between 700 nm and 1 mm, situated between the visible spectrum and microwaves.

    Example

    The snake can find its prey in the dark by sensing infrared.

    Example

    The telescope captures infrared to peer through dense clouds of space dust that block our view of distant stars.

    Usage

    Often used as an uncountable noun when referring to the radiation itself.

    • thermal radiation
  2. 2 using infrared light (adj.)
    B2 Upper Intermediate Technical Science

    describes technology or light that uses the infrared part of the spectrum.

    relating to or using electromagnetic radiation in the infrared spectrum.

    Example

    You can use an infrared remote to change the TV channel.

    Example

    Security teams used infrared cameras to monitor the perimeter of the building during the blackout.

    Usage

    This adjective is non-gradable; something cannot be 'more infrared' than something else.

Origin

From infra- + red.

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