PCA or PCa may refer to:
Medicine and biology
- Patient-controlled analgesia, any method of allowing a person in pain to administer his own pain relief
- Personal Care Assistant/Attendant or Patient Care Assistant, a caregiver who assists a person with day-to-day tasks
- Plate count agar (microbiology), a microbiological growth medium
- Polymerase cycling assembly, a method for the assembly of large DNA oligonucleotides from shorter fragments
- Posterior cerebral artery (neuroscience), a blood vessel to the posterior aspect of the brain (occipital lobe)
- Posterior cortical atrophy, the visual variant of Alzheimer’s disease
- Prostate cancer antigen
- Protein-fragment Complementation Assay, a method for the identification of proteinâ€"protein interactions in biological systems
- Posterior cricoarytenoid muscle, laryngeal muscle involved with opening the vocal chord
Military and government
- Partnership and Cooperation Agreement (EU)
- Permanent Change of Assignment, describes the reassignment of active duty military personnel to a new unit within the same post
- Personal Capability Assessment, see Employment and Support Allowance (UK)
Organizations
Education
- Paris College of Art, an American private university in Paris, France
- Pasig Christian Academy, a school located in Caniogan, Pasig City, Philippines
- Pensacola Christian Academy, a private Christian school in Pensacola, Florida
- Peoples Christian Academy, a private Christian school in Toronto, Ontario, Canada
- Pittsburgh Classical Academy Middle School, a middle school with an academic program that focuses on classical history
- Plano Christian Academy, an Evangelical, non-denominational, private, Classical Christian school supporting grades K-12
- Prestonwood Christian Academy, a private Christian Pre K-12 school in Plano, Texas
- Providence Christian Academy (disambiguation), for multiple schools
Games
- PokerStars Caribbean Adventure, European Poker Tour event
- Professional Chess Association, from 1993 to 1996, a rival organisation to FIDE, the international chess organization
Political
- Parti Communiste Algérien (Algerian Communist Party)
- Partido Comunista de AndalucÃa (Communist Party of Andalusia)
- Partido Comunista de Aragón (Communist Party of Aragon)
- Partido Comunista de la Argentina (Communist Party of Argentina)
Religion
- Presbyterian Church in America, a Protestant Christian denomination, the second largest Presbyterian body in the United States after the Presbyterian Church (U.S.A.)
- Presbyterian Church of Australia, the largest Presbyterian denomination in Australia
Sports
- Positive Coaching Alliance, provides training workshops to schools and youth sports organizations (USA)
- Professional Cricketers' Association, representative body of past and present first class cricketers in England and Wales
- Punjab Cricket Association Stadium, Mohali, India
Other
- Police Complaints Authority (disambiguation)
- Porsche Club of America, an organization of Porsche enthusiasts in the United States and Canada
- POSC Caesar Association, a standardization organization, custodian of ISO 15926
- Predator Conservation Alliance (USA), founded in 1991, a conservation group based in Bozeman, Montana
Science and technology
- Probabilistic Cellular Automata (Math/Stochastic Processes)
- Principal component analysis, a statistical procedure
- para-Chloroamphetamine or 4-Chloroamphetamine
- Printed Circuit Assembly or Printed circuit board
- Protocatechuic acid, a polyphenol antioxidant
- Pyroglutamic acid, an amino acid derivative
- Propulsion Controlled Aircraft, a computer-assisted propulsion control system that enables the safe landing of an aircraft when its normal control surfaces such as elevators, rudders, and ailerons are disabled.
Computers
- Physical configuration audit, in configuration management
- Polymorphous Computer Architectures, see Josep Torrellas
Other uses
- Peanut Corporation of America, a peanut processor forced out of business after being found to be the source of a massive salmonella outbreak in the United States
- Permanent Court of Arbitration, based in The Hague, the oldest international institution for dispute resolution
- Personal carbon allowance, a ration of allowed carbon emissions for individuals, designed to help address human-caused global warming
- Production Code Administration, a division of the Motion Picture Association of America
- Prompt Corrective Action, a law which requires penalties for banks which don't meet their capital requirements
- Pacific Coast Academy, the fictional school in which the Nickelodeon television series Zoey 101 is set
- Packaging Corporation of America, a containerboard and corrugated packaging products company in the United States
- People's Choice Awards, an American awards show recognizing popular culture, held annually and voted on by the general public
