List of acronyms: P

This list contains acronyms, initialisms, and pseudo-blends  that begin with the letter P.

For the purposes of this list:

• acronym = an abbreviation pronounced as if it were a word, e.g., SARS = severe acute respiratory syndrome, pronounced to rhyme with cars
• initialism = an abbreviation pronounced wholly or partly using the names of its constituent letters, e.g., CD = compact disc, pronounced cee dee
• pseudo-blend = an abbreviation whose extra or omitted letters mean that it cannot stand as a true acronym, initialism, or portmanteau (a word formed by combining two or more words).

(a) = acronym, e.g.: SARS – (a) Severe acute respiratory syndrome

(i) = initialism, e.g.: CD – (i) Compact disc

(p) = pseudo-blend, e.g.: UNIFEM – (p) United Nations Development Fund for Women

(s) = symbol (none of the above, representing and pronounced as something else; for example: MHz – Megahertz)

(Main list of acronyms)

• Top
• P0–9 PA PB PC PD PE PF PG PH PI PJ PK PL PM PN PO PP PQ PR PS PT PU PV PW PX PY PZ

• p – (s) pico
• P – (s) Peta – Phosphorus

P0–9

• P2P – (i) Peer-to-peer (networking)
• P3I or P³I – (i) PrePlanned Product Improvement

PA

• pa – (s) Punjabi language (ISO 639-1 code)
• pA – (s) picoampere
• Pa
  • (s) pascal
  • Protactinium
• PA
  • (a/i) Pamela Anderson
  • (s) Panama (ISO 3166 digram)
  • Paraguay (FIPS 10-4 country code)
  • (i) Partial Agonist
  • (s) Pennsylvania (postal symbol)
  • petampere
  • (i) PolyAmide (Nylon)
  • Prince Albert piercing
  • Public Address (vocal amplification system)
  • Public Affairs
• PA 6 – (s) Nylon 6 (PolyAmide) (similarly for PA 11, 12, 46, 66, 610)
• PAA – (i) Position Area for Artillery
• PAB – (s) Panamanian balboa (ISO 4217 currency code)
• PABX – (p) Private Automated Branch eXchange (company phone system)
• PAC
  • (i) Pan Africanist Congress
  • (a) Partial Solar Calibrator
  • Patriot Advanced Capabilities
  • Political action committee
  • (a/i) Primary Auditory Cortex
• PACOM – (p) (U.S.) Pacific Command
• PADD
  • (a) Personal Access Display Device (as seen in the Star Trek franchise)
  • Petroleum Administration for Defense Districts, used for data collection in the U.S. petroleum industry
• PADI – (a) Professional Association of Diving Instructors
• PAEK – (i) PolyArylEtherKetone
• PAFC – (i) Plymouth Argyle Football Club
• PAH – (i) Polycyclic aromatic hydrocarbon
• PAHO – (i) Pan American Health Organization
• PAI
  • (i) PolyAmide Imide
  • Pre-Approval Inspection (pharma)
• PAK – (s) Pakistan (ISO 3166 trigram)
• Pakistan – (p) Punjab, Afghan states, Kashmir, sIndh, baluchiSTAN
• PAL
  • (a) Phase Alternating Line (TV standard)
  • (p) Philippine Airlines
• PAM – (a/i) Precision Attack Missile
• Pamida – (p) Patrick, Michael, and David, sons of the department store chain's co-founder Jim Witherspoon
• PAMELA
  • (a) Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics
  • (a) Pedestrian Accessibility and Movement Environment Laboratory
• pan – (s) Punjabi language (ISO 639-2 code)
• PAN
  • (s) Panama (ISO 3166 trigram)
  • (a) Partai Amanat Nasional (Indonesian, "National Mandate Party") – Indonesian political party
  • Partido Acción Nacional (Spanish, "National Action Party") – political parties in El Salvador, Mexico, and Nicaragua
  • Partido de Avanzada Nacional (Spanish, "National Advancement Party") – Guatemalan political party
  • Personal Area Network
  • (i) PolyAcryloNitrile
  • (a) Programa de Asistencia Nutricional (Spanish, "Nutritional Assistance Program") – U.S. federal program for nutritional needs of poor families in Puerto Rico
• PANS – (a) Pretty Advanced/Awesome Network Services (cf. POTS)
• Pan-STARRS – (p) Panoramic Survey Telescope And Rapid Response System
• PAO
  • (i) Panathinaikos Athlitikos Omilos (Greek: Παναθηναϊκός Αθλητικός Όμιλος, "Pan-Athenian Athletic Club")
  • Public Affairs Officer
• PAOK – (i) Panthessalonikeios Athlitikós Ómilos Konstantinoupoliton (Greek Πανθεσσαλονίκειος Αθλητικός Όμιλος Κωνσταντινοπολιτών, "Pan-Thessalonian Athletic Club of Constantinopolites")
• PAPI – (a) Precision Approach Path Indicator (aviation)
• PAR – (s) Paraguay (IOC and FIFA trigram, but not ISO 3166)
• PARC – (a) Palo Alto Research Center
• PAROS – (a) Prevention of an Arms Race in Outer Space (treaty)
• PARP – (i) (NATO Partnership for Peace) Planning And Review Process
• PARWIG – (a) Power Augmented Ram Wing In Ground (aeroplane wing shape)
• PAS – See entry
• PASA – (i) PolyAmide, Semi-Aromatic (Nylon)
• PASGT – (i) Personnel Armor System, Ground Troops
• PASR – (i) Personnel Accounting and Strength Reporting
• PATH – (a) Port Authority Trans-Hudson
• PAWS
  • (a) Phased Array Warning System
  • Progressive Animal Welfare Society
• PAYD – (a) Pay As You Drive
• PAYE – (a) Pay As You Earn

PB

• Pb – (s) Lead (Latin Plumbum)
• PB – (p) PolyButylene
• PBA
  • (i) Philippine Basketball Association
  • Professional Bowlers Association
• PBB – (p) PolyBrominated Biphenyl
• PBCK – (i) Problem Between Chair and Keyboard (computer help desk in-joke)
• PBD – (p) PolyButaDiene
• PBDE – (i) PolyBrominated Diphenyl Ether
• PBI – (p) PolyBenzImidazole
• PBN – (p) PolyButylene Naphthalate
• PBOH – (i) Please Become Old History
• PBR
  • (i) Pabst Blue Ribbon (beer brand)
  • Professional Bull Riders
• PBS
  • (i) Pharmaceutical Benefits Scheme (Australia)
  • Public Broadcasting Service (U.S.)
  • Public Broadcasting Services (Malta)
• PBRT - may stand for: Physically Based Raytracing, an open source software rendering system for physically correct image synthesis.
• PBT – (p) PolyButylene Terephthalate
• PBX – (p) Private Branch eXchange (company phone system)

PC

• pC – (s) picocoulomb
• PC
  • (s) petacoulomb
  • U.S. Pacific Islands Trust Territory (ISO 3166 digram; obsolete 1986)
  • (i) Personal computer
  • Player Character (roleplaying)
  • Politically Correct / Political Correctness
  • post cibum (Latin, "after meals")
• PCAS – (i) Planet-Crossing Asteroid Survey
• PCB – see entry
• PCC
  • (i) NATO Partnership Coordination Cell
  • Posterior Cingulate Cortex
  • Pre-Command Course
  • Presidents Conference Committee
• PCCB – (i) Porsche Ceramic Composite Brake
• PCCIP – (i) President's Commission on Critical Infrastructure Protection
• PCE – (p) PerChlorEthylene
• PCI
  • (s) U.S. Pacific Islands Trust Territory (ISO 3166 trigram; obsolete 1986)
  • (i) Peripheral Component Interconnect (computer bus)
• PCIe – (i) Peripheral Component Interconnect Express (computer bus)
• PCL – (i) Passive Coherent Location
• PCMCIA – (i) Personal Computer Memory Card International Association (People Can't Memorise Computer-Industry Acronyms)
• PCN – (s) Pitcairn Islands (ISO 3166 trigram)
• PCP
  • (p) phencyclidine
  • Pneumocystis jiroveci pneumonia (formerly Pneumocystis carinii)
  • (i) Probabilistically Checkable Proof
• PCPI – Physician Consortium for Performance Improvement (AMA)
• PCR – (i) Polymerase chain reaction
• PCSSD - (p) Pulaski County Special School District
• PCT
  • (i) Pacific Crest Trail
  • Patent Cooperation Treaty
• PCTE
  • (i) Portable Common Tool Environment
  • (i) Punjab College of Technical Education
• PCZ – (s) Panama Canal Zone (ISO 3166 trigram; obsolete 1980)

PD

• Pd – (s) Palladium
• PD
  • (i) per diem (Latin: (calculated) by the day)
  • Point of Departure
  • Police Department
  • Postal District
  • Potential Difference
  • Principal Deputy
  • Privatdozent
  • Public domain
• PD – (i) Product Director—Example: CERDEC Product Director C4ISR and Network Modernization
• PDA
  • (i) Personal Digital Assistant
  • Predicted Drift Angle
  • Public Display of Affection
  • Push-Down Automaton
• PDD
  • (i) Past Due Date
  • Presidential Decision Directive
• PDF
  • (i) Panama[nian] Defense Forces (abolished 1990)
  • Portable Document Format
  • Principal Direction of Fire
• PDG
  • (i) President Director General
  • Product Development Group
• PDL
  • (i) Premier Development League (U.S. minor soccer league)
  • Pure Dumb Luck (Texan punk band)
• PDN – (i) Pull-Down Network
• PDP
  • (i) Programmable Data Processor
  • Performance Development Plan^[1]
• PDQ
  • (i) Pre-Defined Queries (Siebel packages)
  • Pretty Damn Quick
• PDRY – (i) People's Democratic Republic of Yemen (obsolete since 1990)
• PDT – (i) Pacific Daylight [Saving] Time (UTC-7 hours)
• PDU
  • (i) Police Dog Unit
  • Power Distribution Unit
  • Protocol Data Unit
• PDVSA – (a/i) Petróleos de Venezuela, S.A. (Spanish, "Venezuelan Petroleum Company")

PE

PE - Professional Engineer

• PE – (s) Ice Pellets (old style METAR Code) – Peru (ISO 3166 and FIPS 10-4 country code digram) – (i) Physical Education – Premature Ejaculation – (s) Prince Edward Island (postal code) – Price to Earning ratio (used for equity shares) – Plant Extract
• PEBCAC – (a) Problem Exists Between Chair and Computer (IT help desk in-joke)
• PEBKAC – (a) Problem Exists Between Keyboard and Chair (ditto)
• PEEK – (i) PolyEtherEtherKetone
• PEET – (a) Partnerships for Enhancing Expertise in Taxonomy
• PEGIDA – (a) Patriotische Europäer gegen die Islamisierung des Abendlandes (German, "Patriotic Europeans Against the Islamization of the West")
• PEI – (i) Prince Edward Island – PolyEtherImide
• PEK – (i) PolyEtherKetone
• PEN
  • (s) Peruvian sol (ISO 4217 currency code)
  • (i) Poets, Essayists and Novelists, the original meaning of the initialism of the organization now known as PEN International
  • PolyEthylene Naphthalate
• PEO – (i) Παγκύπρια Εργατική Ομοσπονδία (Greek for "Pancyprian Federation of Labour") – Philanthropic Educational Organization – PolyEthylene Oxide – Professional Employer Organization – Professional Engineers Ontario
• PEPFAR – (a) President's Emergency Plan For AIDS Relief
• PER – (s) Peru (ISO 3166 trigram)
• perl – (a) usually lower case Practical Extraction and Report Language
• PES – (i) PolyEtherSulfone
• PEST – (a) UK Public Engagement with Science and Technology
• PET – (a/i) Personal Electronic Transactor – Pierre Elliott Trudeau – Positron Emission Tomography (as in PET scan) – PolyEthylene Terephthalate (plastic) – (a) Preliminary English Test
• PETA – (a/i) pentaerythritol triacrylate – People Eating Tasty Animals – People for the Ethical Treatment of Animals
• PETE – (i) PolyEthyleneTErephthalate
• PETP – (i) PolyEthyleneTerePhthalate

PF

• pF – (s) picofarad
• PF
  • (s) French Polynesia (ISO 3166 digram)
  • petafarad
  • (i) Phenol Formaldehyde (resin)
  • Power forward, a player position in Australian rules football, basketball, and ice hockey
• PFD – (i) Permanent Fund Dividend = personal flotation device
• PFE – (i) Permanent Forest Estate
• PFLAG – (p) Parents, Families and Friends of Lesbians and Gays ("pee-flag")
• PFIY – (a) Please Fix it Yourself ("pee-fiy")
• PFO – (i) Pissed, Fell Over (medical diagnosis in-joke)
• PfP – (i) Partnership for Peace

PG

• pg – (s) picogram
• Pg – (s) petagram
• PG –
  • (i) propylene glycol
  • (s) Papua New Guinea (ISO 3166 digram)
  • (i) Parental Guidance (movie rating)
  • Point guard (basketball position)
• PG-13 – (i) Parental Guidance: Some material may be inappropriate for children under 13 (movie rating)
• PGCE – (p) Postgraduate Certificate in Education
• PGD – (i) Pre-implantation Genetic Diagnosis
• PG&E – (i) Pacific Gas & Electric
• PGENI – (i) Pharmaco-Genetics for Every Nation Initiative
• PGH – (i) Pre-implantation Genetic Haplotyping
• PGK – (s) Papua New Guinea kina (ISO 4217 currency code)
• PGM – (i) Precision-Guided Munition
• PGP – (i) Pretty Good Privacy

PH

• pH – (s) parts of hydrogen (acidity/alkalinity index) – picohenry
• PH – (i) Passive Homing (missile guidance system) – (s) petahenry – Philippines (ISO 3166 digram) – (i) Probability of Hit – Public Health – Purple Heart
• PHA – (p) PolyHydroxyAlkanoate – (i) Potentially Hazardous Asteroid
• Ph.D. – (p) Philosophiæ Doctor (Latin, "Doctor of Philosophy")
• PHL – (s) Philippines (ISO 3166 trigram)
• PHQ - Patient Health Questionnaire
• PHP – (s) Philippine peso (ISO 4217 currency code) – (i) PHP: Hypertext Preprocessor (originally Personal Home Page (Tools))

PI

• pi – (s) Pāli language (ISO 639-1 code)
• Pi – (s) Pebi
• PI – (i) PolyImide – PolyIsoprene – Private Investigator
• PIB – (i) PolyIsoButylene
• PIC – (i) Person In Charge
• PICNIC – (a) Problem In Chair Not In Computer
• PICS – (i) Private Investment Capital Subscription
• PID – (i) Pelvic Inflammatory Disease – (p) Plan Identification Number – Positive Identification – Procedural Identification – (i) Procurement Identification Description
• PIDOOMA– (a/i) Pulled It Directly Out Of My Ass
• PIF – (a/i) Partners in Flight
• PIG – (a) Pipeline Inspection Gauge
• PIGS (also PIIGS or PIIGGS) – (a) Portugal, Italy, Greece, Spain; PIIGS if including Ireland; PIIGGS if including the United Kingdom (Great Britain)
• PIM – (a/i) Parameterized Ionospheric Model – Path of Intended Motion – Pediatric Index of Mortality – Personal Information Manager/Management – Presence and Interworking Mobility – Processor-In-Memory – Program Integration Manager – Protocol Independent Multicast
• PIN – (a) Personal Identification Number
• PINF – (i) People In Need Foundation (Czech charitable organisation)
• PIPA – (a/i) Program on International Policy Attitudes
• PIR – (i) Priority Intelligence Requirement
• PIRA – (a) Provisional Irish Republican Army
• PIREPS – (p) Pilot Reports
• PITA – (a) Pain In The Ass
• P.I - Philippines Islands

PJ

• pJ – (s) picojoule
• PJ – (s) petajoule
• PJHQ – (p) Permanent Joint Headquarters
• PJs – (p) Pajamas ("pee-jayz")

PK

• K – (s) picokelvin
• PK – (s) Pakistan (ISO 3166 and FIPS 10-4 country code digram) – petakelvin – (i) Player Kill[er] – Probability of Kill – (p) PolyKetone – (i) Pulemet Kalashnikova (Russian ПК пулемет Калашникова, "Machinegun Kalashnikov")^[2]
• PKA – (i) Previously Known As – Professionally Known As
• PKE – (i) Partnership of Kindermusik Educators^[3][4][5]
• PKI – (i) Public Key Infrastructure (cryptography)
• PKM – (i) Pulemet Kalashnikova Modernizirovanniy (Russian ПКМ пулемет Калашникова модернизированный, "Machinegun Kalashnikov Modernised")^[2]
• PKMS – (i) Pulemet Kalashnikova Modernizirovanniy Stepanova (Russian ПКМС пулемет Калашникова модернизированный Степанова, "Machinegun Kalashnikov Modernised Stepanova")^[2]
• PKMT – (i) Pulemet Kalashnikova Modernizirovanniy Tankoviy (Russian ПКМТ пулемет Калашникова модернизированный танковый, "Machinegun Kalashnikov Modernised Tank") (a.k.a. PKTM)^[2]
• PKR – (s) Pakistani rupee (ISO 4217 currency code)
• PKT – (i) Pulemet Kalashnikova Tankoviy (Russian ПКТ пулемет Калашникова танковый, "Machinegun Kalashnikov Tank")^[2]
• PKTM – (i) Pulemet Kalashnikova Tankoviy Modernizirovanniy (Russian ПКТМ пулемет Калашникова танковый модернизированный, "Machinegun Kalashnikov Tank Modernised") (a.k.a. PKMT)^[2]
• PKU – (p) Phenylketonuria

PL

• pl – (s) Polish language (ISO 639-1 code)
• pL – (s) picolitre
• PL – (s) Ice Pellets (new style METAR Code) – (s) petalitre – (i) Phase Line (Co-ordination Line) – (s) Poland (ISO 3166 and FIPS 10-4 country code digram)
• PLAF – (a/i) People's Liberation Armed Forces – Pluggable look and feel – Product Line Architecture Framework
• PLAID – (p) Precision Location and Identification
• PLB – (i) Personal Locator Beacon
• PLC – (i) Public Limited Company (British)
• PLCC – (i) Plastic Leaded Chip Carrier (electronics)
• PLD – (i) Probable Line of Deployment
• PLEBS – (i) People Lacking Everyday Basic Skills
• PLF – (i) Parachute Landing Fall
• PLGR – (a) Precision Lightweight GPS Receiver ("plugger")
• pli – (s) Pāli language (ISO 639-2 code)
• PLI – (i) Position Location Information – Private Lands Initiative – Professional Liability Insurance
• PLIF – (a) Planar Laser-Induced Fluorescence
• PLK – (i) Polska Liga Koszykówki (Polish, "Polish Basketball League")
• PLKK – (i) Polska Liga Koszykówki Kobiet (Polish, "Polish Women's Basketball League")
• PLL – (i) Phase-Locked Loop (electronics)
• PLM – (i) Polarized Light Microscope/Microscopy
• PLMBA - (i) Phospholipid Bilayer Microarray
• Pln – (p) Platoon
• PLN – (s) Polish zloty (ISO 4217 currency code)
• PLO – (i) Palestine Liberation Organization
• PLOKTA – (a) Press Lots Of Keys To Abort
• PLP – (i) Platonic Life Partner
• PLS – (i) Palletized Loading System – Personal Locator System
• PLUTO – (a) Pipe Line Under The Ocean
• PLW – (s) Palau (ISO 3166 trigram)

PM

• pm – (s) picometre
• Pm – (s) petametre – Promethium
• PM – (s) Panama (FIPS 10-4 country code) – (i) Perry Mason – Phase Modulation – Post Meridiem (Latin "after noon") – Prime Minister – Project Manager – (s) Saint Pierre and Miquelon (ISO 3166 digram)
• PMC – (i) Primary Motor Cortex
• PMCS – (i) Partial Mission Capable Supply (SM&R code) – Power Management Control System – Professional Military Comptroller School
• PME – (i) Professional Military Education
• PMHT – (i) Pardon My Hashtag (Also #PMHT)
• PMI – (i) Positive Material Identification
• PMID – (p) PubMed Identifier
• PMMA – (i) PolyMethylMethAcrylate
• PMOS – (i/a) P-type/Positive Metal-Oxide-Semiconductor transistor ("pee-moss")
• PMS – (i) Premenstrual Syndrome
• PMSC – (i) NATO Political-Military Steering Committee on Partnership for Peace
• PMSL – (i) Piss Myself Laughing (Internet shorthand)
• PMT - Premenstrual Tension (UK) (see Premenstrual Syndrome)

PN

• pN – (s) piconewton
• PN
  • (s) petanewton
  • Pitcairn Islands (ISO 3166 diagram)
• PNAC – (i) Project for the New American Century
• PNC
  • (i) Palestinian National Council
  • Palmerston North City (cf. PNC, a New Zealand rapper from this city)
  • Pittsburgh National Corporation, one of the two companies that merged into today's PNC Financial Services
  • Provident National Corporation, the other company that merged into PNC Financial Services
• PNF – (i) Pilot Not Flying (aviation)
• PNG
  • (s) Papua New Guinea (ISO 3166 trigram)
  • (i) Portable Network Graphics
• PNP
  • (i) Partido Nuevo Progresista
  • Plug 'N' Play/Pray
  • Positive Negative Positive
• PNS – (s) Pensacola, Florida (IATA airport code)
• PNVS – (i) Pilot Night Vision Sensor
• PNH
  • (i) Paroxysmal nocturnal hemoglobinuria
  • Police Nationale d'Haïti (French, "National Police of Haiti")

PO

• Po – (s) Polonium
• PO
  • (s) Dust Devil (METAR Code)
  • (i) per os (Latin, "by mouth")
  • (s) Portugal (FIPS 10-4 country code)
• PO – (i) Post Office
• PO – (i) Purchase Order
• POCD – (i) Post-Operative Cognitive Dysfunction
• pod – (a) Plain Old Documentation
• POD
  • (i) Payable on Death (banking term, and the full name of American metal band P.O.D.)
  • Point of divergence (alternate or counterfactual history)
  • Port of Debarkation
• POE – (a) Perl Object Environment – (b) Port Of Embarkation (c) Polyol Ester (d) Power Over Ethernet
• POETS – (a) Portable Occultation, Eclipse, and Transit electronic-camera System
• POFF – (a) Plain Old Flat File
• POG – (a) Passionfruit, Orange and Guava
• POGO – (a) Project On Government Oversight
• POI – (i) Program Of Instruction
• POK – (a/i) Plane Of Knowledge
• pol – (s) Polish language (ISO 639-2 code)
• POL
  • (i) Petroleum, Oils and Lubricants
  • (s) Poland (ISO 3166 trigram)
• POLAD – (p) Political Advice
• POM
  • (i) Program Objective Memorandum
  • PolyOxyMethylene
• POMDP – (i) Partially observable Markov decision process
• POP
  • (a/i) Point of Presence
  • Post Office Protocol
  • Progesterone Only Pill
• por – (s) Portuguese language (ISO 639-2 code)
• POR
  • (s) Portugal (FIFA and IOC trigram, but not ISO 3166)
  • (i) Proposed Operational Requirement
• POS
  • (a/i) Point Of Sale terminal (retail industry transaction computers)
  • (i) Piece Of S**t
• POSH – (a) Port Outbound Starboard Home (alleged)
• POTC o PotC – (a) Pirates of the Caribbean
• POSSLQ – Person of the Opposite Sex Sharing Living Quarters
• POT – (a/i) Plane Of Tranquility
• POTS
  • (a) Plain Old Telephone Service (cf. PANS)
  • Postural Orthostatic Tachycardia Syndrome
• POV – (i) Point of view
• POW – (i) Prisoner of war

PP

• pp
  • pages, especially in references, e.g. "A. U. Thor, Title, Journal X, Vol. 1, no. 2 (2010) pp. 13-42."
• PP
  • (s) Papua New Guinea (FIPS 10-4 country code)
  • (i) Passage Point
  • per procurationem (Latin, "by proxy")
• PPA
  • (i) Parahippocampal Place Area
  • PolyPhthalAmide
• PPASC – (i) (U.S.) Plans and Program Analysis Support Center
• PPASSCCATAG - (a) "Proud Parents Against Singles, Seniors, Childless Couples And Teens And Gays", a fictional group formed by Marge Simpson
• PPCLI – (i) Princess Patricia's Canadian Light Infantry (regiment)
• PPG
  • (i) Pittsburgh Plate Glass (the original name of the company now known as PPG Industries)
  • The Powerpuff Girls
• PPL
  • (i) Pakistan Petroleum Limited
  • Pay per lead (marketing)
  • Pennsylvania Power and Light, former name of the U.S. utility company now known as PPL
  • Pfadfinder und Pfadfinderinnen Liechtensteins (German, "Scouts and Guides of Liechtenstein")
  • Phonographic Performance Limited (UK performing rights organisation)
• PPLI – (i) Precise Participant Location & Identification
• ppm – (i) Parts Per Million
• PPM – (i) Parts Per Million
• PPM – (i) Project Planning and Management
• PPO – (i) PolyPhenylene Oxide
• PPP
  • (i) Point-to-Point Protocol
  • Purchasing Power Parity
• PPQ – (i) Pulses Per Quarter (used in music programming, sequencers)
• PPQN – (i) Pulses Per Quarter Note (ditto)
• PPQT – (i) Pre-Production Qualification Test
• PPS
  • (i) post postscriptum
  • Precise/Precision Positioning Service (GPS)
  • PolyPhenylene Sulfide
• PPV – (a) Pay-per-view

PQ

• PQ
  • (s) Province of Québec (obsolete postal code, replaced by QC)
  • (i) Parti Québécois

PR

• Pr – (i) Pastor or Priest
• Pr – (s) Praseodymium
• PR
  • (i) Public Relations
  • (s) Puerto Rico (postal symbol; ISO 3166 digram)
• Prb – (i) Presbyter
• PRBO – (i) Point Reyes Bird Observatory
• PRC – (i) People's Republic of China
• PRD – (i) CERDEC Product Realization Directorate
• PRFG – (s) Partial Fog (METAR Code)
• PRI – (s) Puerto Rico (ISO 3166 trigram)
• PRK – (s) Democratic People's Republic of Korea (ISO 3166 trigram)
• PRM – (i) Personnel Readiness Management
• PRN – (i) pro re nata (Latin, "for the emergency", "as needed")
• PRT
  • (s) Portugal (ISO 3166 trigram)
  • (i) Provincial Reconstruction Team
• PRY – (s) Paraguay (ISO 3166 trigram)

PS

• ps
  • (s) Pashto language (ISO 639-1 code)
  • picosecond
• pS – (s) picosiemens
• Ps – (s) petasecond
• PS
  • (s) Palestinian Territory, Occupied (ISO 3166 digram)
  • (i) Personnel Services
  • (s) petasiemens
  • (i) post scriptum (Latin, "written after")
  • Power Steering
  • Power Supply
  • Public School
• PooS – Poo Sniffer (Internet shorthand)
• PSA
  • (i) Paralysis Society of America
  • Pharmaceutical Society of Australia
  • Pressure-Sensitive Adhesive
  • Production Services Association
  • Prostate Specific Antigen
  • Public Service Announcement
  • Public Service Association
• PSC
  • (i) Personal service corporation
  • Primary Somatosensory Cortex
• PSE – (s) Palestinian Territory, Occupied (ISO 3166 trigram)
• PSG – (i) Pacific Seabird Group
• PSI - (i) Pounds per square inch
• PSI – (a/i) Portable Source Initiative
• PSO
  • (i) Peace Support Operations
  • Primary Standardisation Office (ABCA)
  • Protocol Supporting Organization (of the ICANN)
• PSS – (i) Personnel System Support
• PST – (i) Pacific Standard Time (UTC−8 hours)
• PSU – (i) Pennsylvania State University
• PSV
  • (i) Philips Sport Vereniging (Dutch for "Philips Sports Union")
  • Public Service Vehicle
• PsyOp – (p) Psychological Operations

PT

• pt – (s) Portuguese language (ISO 639-1 code)
• pT – (s) picotesla
• Pt – (s) Platinum
• PT – (s) petatesla – (i) Physical Training (in the Army) – (s) Portugal (ISO 3166 digram)
• PTA – (i) Parent-Teacher Association
• PTAL – (i) Public Transport Accessibility Level
• PTAN –
  • (i) Precision Terrain Aided Navigation
  • (a) (pronounced P-tan) Provider Transaction Access Number
• PTES - (i) People's Trust for Endangered Species
• PTFE – (i) PolyTetraFluoroEthylene
• PTI – (i) Pardon the Interruption
• PTL – (p) Patrol – (i) Primary Target Line
• PTO – (i) Patent and Trademark Office – Please Turn Over
• PTSD – (i) Post-Traumatic Stress Disorder
• PTUI – (a/i) Plain-Text User Interface ("pa-too-ey") (cf CLI)

PU

• Pu – (s) Plutonium
• PU
  • (s) Guinea-Bissau (FIPS 10-4 country code)
  • (i) Polyurethane
  • (s) United States Miscellaneous Pacific Islands (ISO 3166 digram; obsolete 1986)
• Pub – (p) Publication
• PUG – (a/i) PET Users Group
• PUN – (a/i) Pull-Up Network
• PUP – (a/i) Pull-Up Point
• PUR – (s) Puerto Rico (IOC and FIFA trigram, but not ISO 3166)
• pus – (s) Pashto language (ISO 639-2 code)
• PUS – (s) United States Miscellaneous Pacific Islands (ISO 3166 trigram; obsolete 1986)

PV

• pV – (s) picovolt
• PV – (s) petavolt
• PVC – (i) Permanent Virtual Circuit – PolyVinyl Chloride – Premature Ventricular Contraction – Primary Visual Cortex
• PvE – (i) Player versus Environment
• PvP – (i) Player versus Player
• PVR – (i) Personal Video Recorder
• PvZ – (i) Plants vs. Zombies

PW

• pW – (s) picowatt
• PW
  • (s) Palau (postal symbol; ISO 3166 digram)
  • petawatt
• PWA – (i) Pirates With Attitude
• PWBA – (p) Pension and Welfare Benefits Administration
• PwC – (i) PricewaterhouseCoopers (international accounting firm)
• PWC – (i) PieceWise Constant (describing a mathematical function)
• PWL – (i) PieceWise Linear (describing a mathematical function)
• PWLC – (i) PieceWise Linear and Concave/Convex (describing a mathematical function)
• PWP – (i) Plot, What Plot? / Porn Without Plot (denotes plotless, um, "feel-good" stories in online fiction, especially fanfic or erotic fiction)
• PWR – (i) Pressurized Water Reactor
• PWV – (i) Pretoria-Witwatersrand-Vereeniging, the original name for the South African province now known as Gauteng, and still used to refer to the metropolitan agglomeration at the core of the province

PX

• PX – (p) Post eXchange

PY

• PY – (s) Paraguay (ISO 3166 digram) – Person-Year – (i) Portsmouth yardstick
• PYF – (s) French Polynesia (ISO 3166 trigram)
• PYG – (s) Paraguayan guaraní (ISO 4217 currency code)
• PYMWYMI – (a) Put Your Money Where Your Mouth Is

PZ

• PZ – (s) Panama Canal Zone (ISO 3166 digram; obsolete 1980) – (i) Pickup Zone

References

1. Manual de comunicación.
2. http://www.milparade.com/Soderzhaniye.pdf
3. http://www.thepartnershipofkindermusikeducators.blogspot.com
4. "kindermusik-germany.de".
5. "Music Classes for Children and Schools - Kindermusik". Kindermusik.com.