1. The study of the positions and motions of celestial bodies in the belief that they have an influence on the course of natural earthly occurrences and human affairs.
2. Obsolete Astronomy.
[Middle English astrologie, from Old French, from Latin astrologia, from Greek astrologiā : astro-, astro- + -logiā, -logy.]
as′tro·logi·cal (ăs′trə-lŏjĭ-kəl), as′tro·logic adj.
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.