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.]
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Indo-European & Semitic Roots Appendices
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