| Acronym | Meaning |
| PCD | Programmed Cell Death |
| PCDE | Polychlorinated Diphenyl Ethers |
| PCDW | Pluvinage Continuum Distorted Wave ( A Wave Function In Calcns. On Atomic And Molecular Collisions) |
| PCDW | Projectile Continuum Distorted Wave (in Atom Collision Calcns.) |
| PCE | Polychromatic Erythrocytes |
| PCE | Tetrachloroethylene (perchloroethylene Or Perk) |
| PCEM | Point-charge Electrostatic Model |
| PCET | Proton-coupled Electron Transfer |
| PCF | Photonic Crystal Fiber |
| PCF | Pair Correlation Function |
| PCF | Plasma Centrifugal Furnace |
| PCFA | Principal Component Factor Analysis |
| PCFB | Pressurized Circulating Fluidized Bed (gasification Apparatus) |
| PCGC | Parallel Column Gas Chromatography |
| PCGVB | Pairwise Correlated Generalized Valence Bond Method |
| PCI | Peripheral Component Interconnect |
| PCI | Positive-ion Chemical Ionization (mass Spectrometry) |
| PCI | Percutaneous Coronary Intervention |
| PCI | Perturbative Configuration Interaction |
| PCI-80 | Parametrized Configuration Interaction (with Parameter) 80 |
| PCI-X | Parametrized Configuration Interaction (with Parameter) X |
| PCID | Point-charge-induced-dipole (model |
| PCILO | Perturbative Configuration Interaction Using Localized Orbitals |
| PCILOCC | PCILO For Crystal Calculations |
| PCL | Phase Conjugate Laser |
| PCM | Phase Contrast Microscopy |
| PCM | Phase-change Material (in Heat Storage) |
| PCM | Phase-change Medium |
| PCM | Polarizable Continuum Model |
| PCMCIA | Personal Computer Memory Card International Association |
| PCMI | Pellet Cladding Mechanical Interaction |
| PCMO | Precanonical Molecular Orbital |
| PCMT | Protein Carboxyl Methyltransferase |
| PCN | Polychlorinated Naphthalene |
| PCNA | Proliferating Cell Nuclear Antigen |
| PCO | Perturbational Crystal Orbital |
| PCOP | Positron Correlation Polarization (potential) |
| PCOS | Polycystic Ovary Syndrome |
| PCP | Pentachlorophenol (Reg: 87865) |
| PCP | Photoelectric Charging Of Particles |
| PCPAA | Prompt Charged Particle Activation Analysis |
| PCPI | Permanent Committee On Patent Information |
| PCR | Photo-Conductive Resonance |
| PCR | Polymerase Chain Reaction |
| PCR | Principal Component Regression |
| PCS | Permit Compliance System |
| PCS | Photon Correlation Spectroscopy |
| PCSFC | Packed Column Supercritical Fluid Chromatography |
| PCT | Patent Cooperation Treaty |
| PCT | Photoinduced Charge Transfer |