[ rey-dee-uhnt ]
/ ˈreɪ di ənt /


emitting rays of light; shining; bright: the radiant sun; radiant colors.
bright with joy, hope, etc.: radiant smiles; a radiant future.
Physics. emitted or propagated by radiation.
  1. noting a partition line having a series of flamelike indentations formed by ogees joined in zigzags; rayonny.
  2. (of a charge, as an ordinary) having an edge or edges so formed.


Origin of radiant

1400–50; late Middle English < Latin radiant- (stem of radiāns, present participle of radiāre to radiate light, shine), equivalent to radi(us) beam, ray (see radius) + -ant- -ant

Related forms

Synonym study

1. See bright.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for radiantly

British Dictionary definitions for radiantly


/ (ˈreɪdɪənt) /



a point or object that emits radiation, esp the part of a heater that gives out heat
astronomy the point in space from which a meteor shower appears to emanate

Derived Forms

radiantly, adverb

Word Origin for radiant

C15: from Latin radiāre to shine, from radius ray of light, radius
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

Medicine definitions for radiantly


[ rādē-ənt ]


Emitting heat or light.
Consisting of or emitted as radiation.


A point from which light radiates to the eye.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Science definitions for radiantly


[ rādē-ənt ]


Transmitting light, heat, or other radiation. Stars, for example, are radiant bodies.
Consisting of or transmitted as radiation.


The apparent celestial origin of a meteor shower. For example, a point in the constellation Gemini is the radiant of the Geminid meteor shower.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.