- polysiloxane-based thermoplastic elastomer
- polysleeve
- polyslip
- polysome
- polysomic inheritance
- polyspast
- polyspectra
- polyspectrum
- polyspermy
- polyspherical coordinate
- polysphygmograph
- polyspory
- polystele
- polystenobaric
- polystomy
- polystyrene
- polysulfane
- polysulfate
- polysulfide
- polysulfide propellant
- polysulfide rubber
- polysulfide rubber; Thiokol
- polysulfide sealant
- polysulfide silane coupling agent
- polysulfone