What does P stand for?

What does P mean?

P	Provisional Governmental » Military
P	Peninsula Academic & Science » Geology
P	Phosphorus Academic & Science » Chemistry
P	Phosphorus Medical » Laboratory
P	Privilege Community » Law
P	Pseudo Miscellaneous » Unclassified
P	Porsche Governmental » Transportation
P	Possibilities Miscellaneous » Unclassified
P	Paolo Miscellaneous » Unclassified
P	Parity Computing » Databases
P	Pokemon Miscellaneous » Funnies
P	Primavera Miscellaneous » Food
P	Permanente Business » Firms
P	Projected Business » Accounting
P	Paraguay Regional » Countries
P	Penguin Medical » Veterinary
P	Photographic Miscellaneous » Unclassified
P	Poo Miscellaneous » Funnies
P	Parfum Business » Products
P	Penis Medical » Physiology
P	Pico- Academic & Science » Electronics
P	Phenotypic Medical » Human Genome
P	Pumpkin Miscellaneous » Food
P	Pony Medical » Veterinary
P	Pax International » Latin