- The offices of a commander, as of a military unit, from which orders are issued.
- A center of operations or administration.
- The quarters or place of residence, permanent or temporary, of the commander-in-chief of an army.
- The residence of any military chief, or the place from which his orders are issued.
- Hence The place where one chiefly resides or carries on business.
- The quarters or place of residence of any chief officer, as the general in command of an army, or the head of a police force; the place from which orders or instructions are issued; hence, the center of authority or order.
- The main office from which an organization such as a commercial enterprise is managed; -- usually where the chief executive officer works.
- The <xref>military</xref> <xref>installation</xref> from which <xref>troops</xref> are <xref>commanded</xref> and <xref>orders</xref> are <xref>issued</xref>; the military <xref>unit</xref> consisting of a <xref>commander</xref> and his <xref>support</xref> <xref>staff</xref>.
- The <xref>center</xref> of an <xref>organization</xref>'s <xref>operations</xref> or <xref>administration</xref>.
- A place of <xref>concentrated</xref> <xref>activity</xref> or <xref>influence</xref>.
- (plural) a military unit consisting of a commander and the headquarters staff
- the military installation from which a commander performs the functions of command
- (usually plural) the office that serves as the administrative center of an enterprise