1. Full of light; shining. See Synonyms at bright.
2. Relating to or being a hue that has a combination of high lightness and strong saturation.
3. Sharp and clear in tone: a recording with brilliant sound.
4. Glorious; magnificent: the brilliant court life at Versailles.
5. Superb; wonderful: The soloist gave a brilliant performance.
6. Having or showing unusual and impressive intelligence: a brilliant mind; a brilliant solution to the problem. See Synonyms at intelligent.
A precious gem, especially a diamond, finely cut in any of various forms with numerous facets.
[French brillant, present participle of briller, to shine, from Italian brillare, perhaps from brillo, beryl, from Latin bēryllus; see BERYL.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. 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.