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qua·sar (kwāzär′, -sär′, -zər, -sər)
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n.
A compact, extremely bright celestial object whose power output can be hundreds to several thousand times that of the entire Milky Way galaxy. Quasars are among the most distant objects in the universe and are generally considered to be a form of active galactic nucleus.
[From earlier quas(i-stell)ar (radio source).]
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:

    Indo-European Roots

    Semitic Roots

    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.

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