ra·​di·​ate | \ ˈrā-dē-ˌāt How to pronounce radiate (audio) \
radiated; radiating

Definition of radiate

 (Entry 1 of 2)

intransitive verb

1 : to proceed in a direct line from or toward a center
2 : to send out rays : shine brightly
3a : to issue in or as if in rays
b : to evolve by adaptive radiation

transitive verb

1 : to send out in or as if in rays
3 : to spread abroad or around as if from a center


ra·​di·​ate | \ ˈrā-dē-ət How to pronounce radiate (audio) , -ˌāt \

Definition of radiate (Entry 2 of 2)

: having rays or radial parts: such as
a : having ray flowers
b : characterized by radial symmetry : radially symmetrical

Other Words from radiate


radiately adverb

Synonyms & Antonyms for radiate

Synonyms: Verb

Antonyms: Verb

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Examples of radiate in a Sentence

Verb The pain was radiating down my arm. The sun radiates heat and light. Heat radiates from the sun.
Recent Examples on the Web: Verb Some people are simply the center of the wheel of their times, the hub from which spokes of connection radiate in every direction. Ty Burr, WSJ, 27 May 2022 Objects warmer than that will radiate heat to the skin; at high temperatures, this means that the skin will be receiving heat from the environment by direct radiation. The New Yorker, 29 Aug. 2022 Your face turns red because warm, oxygenated blood rushes to the surface of your skin, which helps heat radiate off of it and prevents you from overheating. Jenny Sugar, Outside Online, 26 Aug. 2022 Poland also plans to join the high-speed club with routes planned to radiate from Warsaw to Lodz, Wroclaw and Poznan. Ben Jones, CNN, 6 July 2022 Stuart, like the actor who portrays him, opened himself to Christ, and both men’s sincerity, humility, and devotion radiate from Father Stu, a stirring depiction of faith’s journey that will be spiritual balm for many of those who see it. Kyle Smith, National Review, 12 Apr. 2022 Chest pain is the classic symptom, but other symptoms associated with heart attacks can be much more subtle, such as a pressure or tightness within the chest that can sometimes radiate to the jaw, arms and back. Erika Edwards, NBC News, 21 Aug. 2022 The test image, released to the public in March, showed a brilliant star that appeared to radiate light from six points, a feature of the telescope’s hexagonal mirrors. Corinne Purtill, Los Angeles Times, 11 July 2022 With the men gone, her ideas rip through masses of women eager to see power radiate through circles, rather than up ladders. Hillary Kelly, The Atlantic, 16 June 2022 See More

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

First Known Use of radiate


circa 1619, in the meaning defined at intransitive sense 1


1668, in the meaning defined above

History and Etymology for radiate


Latin radiatus, past participle of radiare, from radius ray

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Time Traveler for radiate

Time Traveler

The first known use of radiate was circa 1619

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Dictionary Entries Near radiate

radiant yellow



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Statistics for radiate

Last Updated

20 Sep 2022

Cite this Entry

“Radiate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/radiate. Accessed 1 Oct. 2022.

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More Definitions for radiate


ra·​di·​ate | \ ˈrā-dē-ˌāt How to pronounce radiate (audio) \
radiated; radiating

Kids Definition of radiate

1 : to send out rays : shine The sun was radiating in the sky.
2 : to come forth in the form of rays Light radiates from shining bodies.
3 : to go out in a direct line from a center Spokes radiate from the center of the wheel.
4 : to spread around from or as if from a center Word radiated that Royce McNabb had sent Ina-Rae Gage a valentine.— Richard Peck, A Year Down Yonder
5 : to show very clearly She radiates confidence.


ra·​di·​ate | \ ˈrād-ē-ˌāt How to pronounce radiate (audio) \
radiated; radiating

Medical Definition of radiate

 (Entry 1 of 2)

intransitive verb

: to issue in or as if in rays : spread from a central point back pain radiating to both upper legs— Tony Miksanek


ra·​di·​ate | \ ˈrād-ē-ət, -ē-ˌāt How to pronounce radiate (audio) \

Medical Definition of radiate (Entry 2 of 2)

1 : having rays or radial parts
2 : characterized by radial symmetry : radially symmetrical

More from Merriam-Webster on radiate

Nglish: Translation of radiate for Spanish Speakers

Britannica English: Translation of radiate for Arabic Speakers


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