- plane waveguide
- plane wave lens
- plane wave solution of Dirac spinor wave equation
- plane wave time domain method
- plane wave time domain method, PWTD
- planform
- plan for national economic development
- Plan for the Popularization of Senior High School Education (2017-2020)
- Plan General de Ordenación de Madrid
- P. Langevin
- P. Langevin, 1872—1946
- planiform
- planigon
- planigraphy
- planimegraph
- planimeter
- planimetering
- planimetric
- planimetrical
- planimetry
- planing of urban fire control
- planisphere
- planispheric astrolabe
- planitia
- Planitia Descensus