- PRI (projector reticle image)
- PRIA (Participatory Research In Asia)
- PRICE (Positivity Responsibility Influences Consequences And Encouragement)
- PRIDE (Parents Ready Involved Desiring Excellence)
- PRIFLY (PRImary FLight Control (Aircraft carriers))
- PRI-FLY (Primary Flying station)
- Pril(l) (Priscilla)
- Prim (Primary (electricity) nuclear, hydro, geothermal, wind, solar)
- PRIME (Pride and Responsibility In My Environment)
- PRIMIR (Product Improvement Management Information Report)
- PRIMS (Physical Readiness Information Management System)
- PRIN (Partnership for Rural Inverness and Nairn)
- PRINCESS (Priceless, Resourceful, Intelligent, Nice, Capable, Exceptional, Strong, Successful)
- PRIO (Peace Research Institute of Oslo)
- PRIS (Phoenix Resource Interface System)
- PRISM (Planning Tool For Resource, Integration, Synchronization, and Management)
- PRISS (Post-Deployment Real Time Interactive Simulation System)
- PRK (Democratic People's Republic of Korea (ISO 3166 trigram))
- PR.K. (Pridie Kalendas ("The Day Before the Calends"))