1. Emitting heat or light: a radiant star.
2. Consisting of or emitted as radiation: radiant heat.
3. Filled with light shining especially as rays; brightly shining: a radiant morning. See Synonyms at bright.
a. Showing or expressing vitality or joy: radiant eyes; a radiant smile.
b. Splendid; glorious: radiant beauty; a radiant future.
1. An object or point from which light or heat rays are emitted.
2. Astronomy The apparent celestial origin of a meteoric shower.
[Middle English, from Latin radiāns, radiant-, present participle of radiāre, to radiate; see RADIATE.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.