parc - phas
- parcel
- parcel method
- parcel theory
- parent cloud
- parhelic circle
- parhelic ring
- parhelion
- parry
- Parry arcs
- parsec
- Parseval's theorem
- partial coherence
- partial correlation
- partial derivative
- partial differential coefficient
- partial differential equation
- partial drought
- partial eclipse
- partial frequency
- partial obscuration
- partial potential temperature
- partial pressure
- partial tide
- partial vacuum
- partial-duration series
- partially polarized wave
- particle
- particle absorption
- particle derivative
- particle radiation
- particle size distribution
- particle velocity
- particulate
- particulate loading
- particulate pollutant
- partition function
- partition of energy
- partly cloudy
- partly occluded
- parts per billion (ppb)
