Why is headquarters plural?

Related questions

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Tags

1. #surroundings
2. #tantum
3. #singular
4. #known
5. #outskirts
6. #headquarters
7. #nouns
8. #composite
9. #plurals
10. #followed
11. #premises
12. #answers
13. #others
14. #plural
15. #meaning
16. #because
17. #either
18. #collective
19. #pluralia
20. #whose
21. #unusual