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verb, ra·di·ate \ˈrā-dē-ˌāt\

Simple Definition of radiate

  • : to go out in a direct line from a central point or area

  • : to move in a specified direction from a source

  • : to send out (something, such as heat or energy) in rays

Source: Merriam-Webster's Learner's Dictionary

Full Definition of radiate


  1. intransitive verb
  2. 1 :  to proceed in a direct line from or toward a center

  3. 2 :  to send out rays :  shine brightly

  4. 3 a :  to issue in or as if in rays b :  to evolve by adaptive radiation

  5. transitive verb
  6. 1 :  to send out in or as if in rays

  7. 2 :  irradiate, illuminate

  8. 3 :  to spread abroad or around as if from a center

Examples of radiate in a sentence

  1. The pain was radiating down my arm.

  2. The sun radiates heat and light.

  3. Heat radiates from the sun.

Origin of radiate

Latin radiatus, past participle of radiare, from radius ray

First Known Use: circa 1619

Rhymes with radiate

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adjective ra·di·ate \ˈrā-dē-ət, -ˌāt\

Definition of radiate

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

radiately adverb


First Known Use of radiate


RADIATE Defined for Kids


verb ra·di·ate \ˈrā-dē-ˌāt\

Definition of radiate for Students


  1. 1 :  to send out rays :  shine <The sun was radiating in the sky.>

  2. 2 :  to come forth in the form of rays <Light radiates from shining bodies.>

  3. 3 :  to go out in a direct line from a center <Spokes radiate from the center of the wheel.>

  4. 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. 5 :  to show very clearly <She radiates confidence.>

Medical Dictionary



verb ra·di·ate \ˈrād-ē-ˌāt\

Medical Definition of radiate

radiated; radiating

  1. intransitive verb

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

  3. transitive verb

  4. :  irradiate



adjective ra·di·ate \ˈrād-ē-ət, -ē-ˌāt\

Medical Definition of radiate

  1. 1:  having rays or radial parts

  2. 2:  characterized by radial symmetry :  radially symmetrical

Seen and Heard

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tending to dismiss important matters

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