# infrared

/ˌɪnfɹɝˈɛd/ (US) · /ˌɪnfɹəɹˈɛd/ (UK)

Source: https://englishreference.com/word/infrared
Updated: 2026-06-20

## Senses

### 1. invisible light/heat

noun · CEFR B2 · Technical

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

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

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

### 2. using infrared light

adjective · CEFR B2 · Technical

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

For teachers: relating to or using electromagnetic radiation in the infrared spectrum.

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

## Examples

- The remote control uses infrared to change the channel.
- Firefighters use infrared cameras to locate people through thick smoke by detecting their body heat.
- By observing the universe in the infrared spectrum, astronomers can peer through dense clouds of cosmic dust that would otherwise obscure the formation of new stars.

---

From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.