| Acronym | Meaning |
| NCP | National Contingency Plan (Superfund) |
| NCP | Net Community Productivity |
| NCPM | Noncritical Phase-matching |
| NCPTT | National Center For Preservation Technology And Training |
| NCRDS | National Coal Resources Data System |
| NCRP | National Council On Radiation Protection |
| NCRPM | National Council On Radiation Protection And Measurements |
| NCS | Notification Of Compliance Status |
| NCSCI | National Center For Standards And Certification Information |
| NCSE | National Council For Science And The Environment |
| NCSRP | National Contaminated Sites Remediation Program |
| NCTN | NASA Commercial Technology Network |
| NCTR | National Center For Toxicological Research |
| NCTTA | National Competitiveness Technology Transfer Act |
| NCV | Nerve Conduction Velocity |
| NCWQ | National Commission On Water Quality |
| ND | Nitrification Denitrification |
| NDA | New Drug Application |
| NDA | Nondestructive Assay |
| NDB | Nucleic Acid Database |
| NDB | Nondefective Bonding |
| NDBEPR | Nitrification-denitrification Biological Excess Phosphorus Removal |
| NDCEE | National Defense Center For Environmental Excellence |
| NDCT | Natural Draft Cooling Tower |
| NDDN | National Dry Deposition Network (US EPA) |
| NDDO | Neglect Of Diatomic Differential Overlap |
| NDE | Nondestructive Evaluation |
| NDF | Neutral Detergent Fiber |
| NDI | Nondestructive Inspection |
| NDIR | Nondispersive Infrared Analysis |
| NDLM | Nondiagonal Lagrange Multiplier |
| NDO | Neglect Of Differential Overlap |
| NDOL(ND0-L) | Neglect Of Differential Overlap-azimutal Quantum Number (of Valence Ao's) |
| NDP | Neutron Depth Profiling |
| NDP | Net Driving Pressure (in Membrane Reverse Osmosis) |
| NDPD | National Data Processing Division |
| NDPK | Nucleoside Diphosphate Kinase |
| NDR | Neg. Differential Resistance |
| NDSC | Network For The Detection Of Stratospheric Change |
| NDSL | Non-Domestic Substances List |
| NDT | Nil Ductility Temperature |
| NDT | Nondestructive Testing |
| NDTT | Nil Ductility Transition Temperature |
| NDUV | Non-dispersive Ultraviolet Analyzer |
| NDWAC | National Drinking Water Advisory Council |
| NDWBA | Normalized Distorted-wave Born Approximation |
| NEA | Nuclear Energy Agency |
| NEA | Negative Electron Affinity |
| NEAR | Near Earth Asteroid Rendezvous |
| NEAT | Near Earth Asteroid Tracking |