1. The production or condition of polarity, as:
a. A process or state in which rays of light exhibit different properties in different directions, especially the state in which all the vibration takes place in one plane.
b. The partial or complete polar separation of the positive and negative electric charges in a nuclear, atomic, molecular, or chemical system.
2. A division into two conflicting or contrasting groups.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 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.