O/R - Originator/Recipient 
OA - Object Adapter 
OA - Office Automation 
OA - Open Access 
OAA - Open Arcade Architecture 
OAD - Open Architecture Driver 
OADG - Open Architecture Development G… 
OAG - Online Airline Guide 
OAG - Open Application Group 
OAGIS - Open Applications Group Intero… 
OAI - Open Applications Interface 
OAI - Open Archives Initiative 
OAIS - Open Archival Information Syste… 
OAK - Object Application Kernel 
OAK - OEM Adaption Kit 
OAM - Object Attribute Memory 
OAM - Operations, Administration and M… 
OARnet - Ohio Academic Resources Netwo… 
OAS - Office Automation System 
OASF - Office Automation System Facili… 
OASIS - Online Application System Inte… 
OASIS - Open And Secure Information Sy… 
OASIS - Organisation for the Advanceme… 
OASIS - Organization for the Advanceme… 
OASYS - Office Automation SYStem 
OAT - Operational Acceptance Testing 
OATS - Office Automation Technology an… 
OAW - Office Activation Wizard 
OAW - Optically Assisted Winchester 
OBA - object behavior analysis