Pt

Pt
Platinum is a lustrous, malleable and ductile metallic element.
PTFE
Abbreviation of Polytetrafluoroethylene, a thermoplastic polymer used for non-stick coatings and bearings.
PTM
Abbreviation of Pulse Time Modulation.
Ptolemy
He believed that Earth was the centre of the universe and that everything orbited it.
Ptolemy′s System
The explanation given by ancient Greek astronomers to the motion of planets around the sky, described in a book by the Greek Ptolemy, around 150 AD.