1. Roman Mythology The god of war.
2. The fourth planet from the sun, having a sidereal period of revolution about the sun of 687 days at a mean distance of 227.9 million kilometers (141.6 million miles) and a mean diameter of approximately 6,794 kilometers (4,222 miles).
[Middle English, from Latin Mārs.]
(click for a larger image)Mars
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.