headquarters

head +‎ quarters

• (Received Pronunciation) IPA^(key): /ˌhɛdˈkwɔːtəz/
• (US) IPA^(key): /ˈhɛdˌkwɔɹtəz/

headquarters (plural headquarters)

1. The military installation from which troops are commanded and orders are issued; the military unit consisting of a commander and his support staff.
2. The center of an organization's operations or administration.
   • 2006, Edwin Black, chapter 1, in Internal Combustion‎:

     As though on an incendiary rampage, the fires systematically devoured the contents of Edison's headquarters and facilities.

3. A place of concentrated activity or influence.

• The word is plural in construction and can take singular or plural verbs.

• HQ, h.q.
• head office

• (US) headquarter