In British naval usage, the term 'port admiral' had two distinct (and somewhat contradictory) meanings, one generic, one specific.
Generic use Historically, 'port admiral' was used as a generic term for the senior naval officer having authority over all commissioned ships and naval personnel stationed at a particular home base or anchorage. (Those appointed as Flag Officers Commanding or Commanding-in-Chief of a particular area or Fleet often functioned as the local port admiral in this sense.) By this definition, the port admiral did not have oversight of the local
Royal Navy Dockyard (if any); Dockyards (including ships laid up '
in ordinary') were overseen by an independent official: usually a resident Commissioner appointed by the
Navy Board (prior to 1832) or an
Admiral-superintendent appointed by the
Admiralty (1832-1971). The distinction is seen in informal correspondence such as the following, dated 1837:
"The Devonport regatta ... was attended by the Port-Admiral, the Admiral-Superintendent of the Dockyard ... and other persons of consideration." In practice, the offices of port admiral and admiral-superintendent were sometimes combined.
Specific use In 1971, the remaining Admirals-Superintendent of HM Dockyards were redesignated as Port Admirals; unlike the above use of the term, this was an official designation. This reflected a consolidation of previously distinct command roles, and coincided with the appointment of civilian Dockyard General Managers to oversee work within the Dockyards across all departments.
Current use Today, both uses of the term are obsolete (as far as current naval practice is concerned) as the equivalent appointments are not of flag-officer rank. ==United States Navy==