[verb rey-dee-eyt; adjective rey-dee-it, -eyt]

verb (used without object), ra·di·at·ed, ra·di·at·ing.

verb (used with object), ra·di·at·ed, ra·di·at·ing.

to emit in rays; disseminate, as from a center.
(of persons) to project (joy, goodwill, etc.).


Nearby words

  1. radiant heating,
  2. radiant intensity,
  3. radiantly,
  4. radiata,
  5. radiata pine,
  6. radiate crown,
  7. radiate ligament of rib,
  8. radiation,
  9. radiation belt,
  10. radiation biology

Origin of radiate

First recorded in 1610–20, radiate is from the Latin word radiātus (past participle of radiāre to radiate light, shine). See radiant, -ate1

Related forms
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for radiability


verb (ˈreɪdɪˌeɪt)

Also: eradiate to emit (heat, light, or some other form of radiation) or (of heat, light, etc) to be emitted as radiation
(intr) (of lines, beams, etc) to spread out from a centre or be arranged in a radial pattern
(tr) (of a person) to show (happiness, health, etc) to a great degree

adjective (ˈreɪdɪɪt, -ˌeɪt)

having rays; radiating
(of a capitulum) consisting of ray florets
(of animals or their parts) showing radial symmetry
adorned or decorated with raysa radiate head on a coin

Word Origin for radiate

C17: from Latin radiāre to emit rays

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for radiability
Online Etymology Dictionary, © 2010 Douglas Harper

Medicine definitions for radiability




The property of being radiable.




To spread out in all directions from a center.
To emit or be emitted as radiation.
Related formsradi•a′tive adj.

The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.