title: O6
text: # O6
  
  O6 or O-6 may refer to:
  
  * LNER Class O6, a class of British steam locomotives
  * O6 star, a subclass of O-class stars
  * OceanAir IATA airline designator
  * O-6, a pay grade in the US uniformed services:
     * Colonel in the Army, Marine Corps, Air Force, and Space Force
     * Captain in the Navy, Coast Guard, Public Health Service Commissioned Corps, and NOAA Commissioned Officer Corps
  * the "Occupied 6", an Irish republican euphemism for Northern Ireland
  * USS O-6 (SS-67), an O-class submarine of the United States Navy
  