- paid attendance (1887)
- palm ball (1905)
- pan (home plate) (1888)
- paper team (1891)
- part-time player (1924)
- pennant (1872)
- pennant fever (1885)
- pennant race (1875)
- percentage baseball (1915)
- perfect game (1904)
- phantom double play (1953)
- pickoff play (1910)
- pickoff throw (1920)
- pill slinger (1908)
- pinch hitter (1896)
- pinch runner (1908)
- pinpoint control (1941)
- pitcher’s best friend (for double play) (1949)
- pitcher’s duel (1884)
- pitchers and catchers report (1887)
- pitcher’s mound (1903)
- pitching coach (1904)
- pitching staff (1888)
- place hitter (1888)
- place hitting (1884)
- plate appearance (1911)
- plate discipline (1959)
- platoon advantage (1957)
- play-by-play (1888)
- play out the string (1878)
- player to be named later (1911)
- potential winning run (1923)
- power hitter (1919)
- pull hitter (1925)
- Punch-and-Judy hitter (1940)
