Billie J. Farrell in the context of "Captain (United States O-6)"

In the United States Navy, United States Coast Guard, United States Public Health Service Commissioned Corps (USPHS Corps), and National Oceanic and Atmospheric Administration Commissioned Officer Corps (NOAA Corps), captain is the senior-most commissioned officer rank below that of flag officer (i.e., admirals). The equivalent rank is colonel in the United States Army, Air Force, Space Force, and Marine Corps.

Reflecting its nautical heritage, the term captain is used as a military title by officers of more junior rank who command a commissioned vessel of the Navy, Coast Guard, or National Oceanic and Atmospheric Administration (NOAA) of patrol boat size or greater. Officers below O-6 who command aviation squadrons (typically O-5 commanders) usually use the less formal title "skipper".