infrared

adjective in·fra·red \ ˌin-frə-ˈred , -(ˌ)frä- , -fə- \
Updated on: 10 Nov 2017

Definition of infrared

1 : situated outside the visible spectrum at its red end used of radiation having a wavelength between about 700 nanometers and 1 millimeter
2 : relating to, producing, or employing infrared radiation
  • infrared therapy
3 : sensitive to infrared radiation
  • infrared sensors that detect body heat

infrared

noun

Recent Examples of infrared from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'infrared.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of infrared

1881


INFRARED Defined for English Language Learners

infrared

adjective

Definition of infrared for English Language Learners

  • : producing or using rays of light that cannot be seen and that are longer than rays that produce red light


INFRARED Defined for Kids

infrared

adjective in·fra·red \ ˌin-frə-ˈred \

Definition of infrared for Students

: being, relating to, or producing rays like light but lying outside the visible spectrum at its red end

Medical Dictionary

1

infrared

adjective in·fra·red \ ˌin-frə-ˈred \

medical Definition of infrared

1 : lying outside the visible spectrum at its red end used of radiation having a wavelength between about 700 nanometers and 1 millimeter
2 : relating to, producing, or employing infrared radiation
  • infrared therapy

2

infrared

noun

medical Definition of infrared

: infrared radiation


Seen and Heard

What made you want to look up infrared? Please tell us where you read or heard it (including the quote, if possible).

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

WORD OF THE DAY

to remove or wipe out

Get Word of the Day daily email!

Test Your Vocabulary

Find the Cousins

  • a-large-tree-with-many-branches
  • Which pair shares a common word ancestor?
How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!

TAKE THE QUIZ
Word Winder's CrossWinder

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!