1. often Sun The star around which Earth and other planets orbit. It provides heat and light to Earth. It has a mean distance from Earth of about 150 million kilometers (93 million miles), a diameter of approximately 1,391,000 kilometers (864,000 miles), and a mass about 333,000 times that of Earth.
2. A star that is the center of a planetary system.
3. The radiant energy, especially heat and visible light, emitted by the sun; sunshine.
4. A sunlike object, representation, or design.
v. sunned, sun·ning, suns
To expose to the sun's rays, as for warming, drying, or tanning.
To expose oneself or itself to the sun.
in the sun
In the public eye.
under the sun
On the earth; in the world.
[Middle English, from Old English sunne; see sāwel- in the Appendix of Indo-European roots.]
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.