a. A military unit typically consisting of a headquarters and two or more companies, batteries, or similar subunits.
b. A large body of organized troops.
2. A great number: battalions of ants.
[French bataillon, from Old French, from Italian battaglione, augmentative of battaglia, from Vulgar Latin *battalia; see BATTLE.]
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:
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