| Acronym | Definition |
|---|
| P1➣Primary 1 (various locations) |
| P1➣Phase One (superbike team) |
| P1➣Player 1 (video games) |
| P1➣PalmOne |
| P1➣Priority One |
| P1➣Politics1 (website) |
| P1➣Proposition One (grassroots nuclear disarmament organization) |
| P1➣Pentium One (Intel CPU) |
| P1➣Pokémon #1 |
| P1➣MHS X.419 Message Transfer Protocol |