- pi-prime
- piriform
- PI-ring
- PIR (= principal ideal ring)
- pi-separable group
- pi-solvable group
- Pisot, Ch.
- Pisot constant
- Pisot number
- Pisot sequence
- Pisot-Vijayaraghavan constant
- pi-squared
- pi-system
- pitch
- Pitcher, E.
- pitchfork bifurcation
- pitching
- pitching angle
- pitch of a helix
- pit-filling problem
- Pitiscus, B.
- Pitman efficiency
- Pitman, E.J.G.
- Pitman estimate
- Pitman estimator