Office of Science and Technology（美国）科学技术局 Original Sound Track影视原声大碟 Online Service Provider在线服务供应商 On-Screen Takeoff (construction planning)屏幕上的起飞(规划建设) Odonata Survey of Texas春的调查德克萨斯州 Open Source Teaching开放源代码的教学 Objective, Strategy, Tactics (business/marketing)目标、策略、战术(商业/销售) Observatoire des Sciences et Techniques (French: science and technology observatory)Observatoire des科学等技术(法国:科技观测站) Optical Standards Tester (Carcadiant Systems)标准测试(Carcadiant光学系统) Old Spanish Trail老西班牙小径上 Office of the Secretary of Transportation办公室的秘书的交通工具 Outer Space Treaty外层空间条约 Operational Suitability Test运转适应性试验 On Second Thoughtadj. 经过重新考虑(在仔细考虑以后) Over-Stress TestOver-Stress测试