Vietnam War Glossary of Terms, Abbreviations and Acronyms

O
O&MOperations and Maintenance
O&MAOperation and Maintenance Appropriation
O&MAOperations and Maintenance, Army
O&MFOperations and Maintenance, Air Force
O&MNOperations and Maintenance, Navy
O&TOrganization and Training
O&T(OT)Organization and Training Directorate
O/HOn Hand
OAObjective Area
OASAOffice of the Assistant Secretary of the Army
OASDOffice of the Assistant Secretary of Defense
OASD(ISA)Office of the Assistant Secretary of Defense for International Security Affairs
OASD(PA)Office of the Asst SECDEF, Public Affairs
OASD(SA)Office of the Assistant Secretary of Defense (Systems Analysis)
OASD/ISAOffice of the Assistant Secretary of Defense for International Security Affairs
OASD/PAOffice of the Assistant Secretary of Defense, Public Affairs
OASD/SAOffice of the Assistant Secretary of Defense, Science Advisor
OBOrder of Battle
OB/GYNObstetrics/Gynecology
OBNProject Letter Designation
OCBOperations Coordinating Board
OCEOffice of Civil Engineer
OCEOffice of the Chief of Engineers
OCOOffice of Civil Operations
OCOOffice of the Chief of Ordnance
OCO/PSDOffice of Civil Operations/Psychological Directorate
OCROptical Character Reader
OCRDOffice of the Chief Rural (formerly Revolutionary) Development
OCSOfficer Candidate School
OFCOffice
OFFOfficer
OHOn Hand
OICOfficer-in-Charge
OICCOfficer-in-Charge of Construction (USN)
OIROther Intelligence Requirements
OJTOn the Job Training
OMOrganizational Maintenance
OMAOperation and Maintenance Appropriation
OMAOperations and Maintenance, Army
OMAFOperations and Maintenance, Air Force
OMNOperations and Maintenance, Navy
OOMAOgden Air Materiel Area
OPObservation Post
OP&AOperations Plans and Analysis
OPCONOperational Control/Condition
OPFOfficial Personnel Folder(s)
OPLANOperation(s) Plan
OPMOffice of the Prime Minister
OPMGOffice of Provost Marshal General
Opn/OPNOperation
OPORDOperations Order
OPROffice Pricing Responsibility
OPREPMessage report in joint operational reporting system
OPSECOperations Security
OPTAROperating Target(s)
OROperational Ready/Operational Readiness
OR/TNGOperational Ready/Training
Ord/ORDOrdnance
OREOperational Readiness Exercise
ORIOperational Readiness Inspection
ORPSOverseas and Return Placement Start
OSAOffice Secretary of the Army
OSAOffice of the Special Assistant (United States Mission - CIA)
OSAOffice of the Special Assistant to the Ambassador (US Embassy)
OSAOperations Systems Analysis Office
OSA (PA)Office of the Secretary of the Army (Public Affairs)
OSDOffice of the Secretary of Defense
OSD (DIO)Office of the Secretary of Defense (Director of Information Operations)
OSD (I&L)Office of the Secretary of Defense (Installation and Logistics)
OSD (ISA)Office of the Secretary of Defense (International Security Affairs)
OSD (PA)Office of the Secretary of Defense (Public Affairs)
OSD/ARPARDFUVProjects Agency, Research and Development Field Unit, Vietnam
OSIOffice of Special Investigations (USAF)
OSPOff-shore Procurement
OSSOverseas switchboards
OSTOrder and Shipping Time
OTCOfficer in Tactical Command
OTIGOffice of the Inspector General
OTPMGOffice of the Provost Marshal General


SOURCES
A Study of Strategic Lessons Learned in Vietnam
Defense Attache Saigon: RVNAF Quarterly Reports
MACV Command Histories
Project RED BARON I: Air-to-Air Encounters in Southeast Asia
Vietnam Pacification Studies #1

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