| PAST | Association to Preserve African American Society, History, and Tradition, Inc | 保护非裔美国人社会、历史和传统协会 |
| PAST | Pilot Activated Self Test (avionics) | 飞行员激活自检（航空电子设备） |
| PAST | Projection Approximation Subspace Tracking | 投影近似子空间跟踪 |
| PAST | Progressively Adaptive Sub-Tree | 渐进自适应子树 |
| PAST | Parakeet Autism Syndrome | 鹦鹉自闭症综合征 |
| PAST | Physical Ability and Stamina Test | 体能和耐力测试 |
| PAST | International Symposium on Phased Array Systems and Technology | 相控阵系统与技术国际研讨会 |
| PAST | Perturbation Approximate Sensitivity Technique | 摄动近似灵敏度技术 |
| PAST | Phased Array Systems and Technology (Conference) | 相控阵系统与技术（会议） |
| PAST | Paleo-Anthropology Scientific Trust (South Africa) | 古人类学科学信托基金（南非） |
| PAST | Parents And Students Together | 家长和学生一起 |
| PAST | pasta | 意大利面食 |
| PAST | pasterurize | 巴氏杀菌 |
| PAST | Parents Against Speeding Teens | 家长反对青少年超速 |
| PAST | Pre Amp Signal Transfer | 前置放大器信号传输 |
| PAST | Principles Assumptions Steps And Techniques | 原则、假设、步骤和技巧 |