text: Acronyms, Abbreviations, and Country Codes
  Bolded entries apply only to the Army. An asterisk (*) marks terms shown in chapter 1.
  NWP Navy warfare publication
  —O—
  O&M operation and maintenance
  OA *objective area, *operational area
  OAKOC observation and fields of fire, avenues of approach, key terrain,
  obstacles, and cover and concealment [military aspects of
  terrain]
  OB *order of battle
  OCA *offensive counterair
  OCO *offensive cyberspace operations
  OCONUS outside the continental United States
  OCS *offensive space control, *operational contract support
  OE *operational environment
  OGA other government agency
  OHDACA Overseas Humanitarian, Disaster, and Civic Aid
  OIC officer in charge
  OMA Operations and Maintenance, Army
  OP observation post
  OPCON *operational control
  OPDS *offshore petroleum distribution system
  OPE *operational preparation of the environment
  OPIR *overhead persistent infrared
  OPLAN *operation plan
  OPNAVINST Chief of Naval Operations instruction
  OPORD *operation order
  OPSEC *operations security
  OPTEMPO operating tempo
  ORSA operations research and systems analysis
  OSC *on-scene commander
  OSD Office of the Secretary of Defense
  OSHA Occupational Safety and Health Administration
  OSINT *open source intelligence
  OSUT one station unit training
  —P—
  PA *public affairs, personnel accountability
  PAA *position area for artillery
  PAG *public affairs guidance
  PAO public affairs officer
  PB *peace building
  PBO property book officer
  PCC precombat check
  PCI precombat inspection
  PCS permanent change of station
  PDSS predeployment site survey
  PE *preparation of the environment
  PFC private first class
  PGM *precision-guided munition