pentahedral - piling up
- persistence of bed
- persistent
- persistent fossil
- persistent fracture
- persistent lode
- persistent mineral
- persistent reflection
- persistent reflector
- personal commitments
- personal computer
- personal dust exposure monitor
- personal safety
- personnel
- personnel safety
- perspective axis
- perspective photograph
- perstratal alluvium
- perthite
- perthitic
- perthitic intergrowth of feldspar