| NIMBY | not in my backyard |
|---|---|
| NIMH | National Institute of Mental Health |
| NIMH-ECA | NIMH-Epidemiologic Catchment Area |
| NIMP | National Intern Matching Program |
| NIMR | National Institute for Medical Research |
| NIMS | National Infant Mortality Surveillance |
| NINCDS | National Institute of Neurological and Communicative Disorders and Stroke |
| NINCDS/ADRDA | National Institute of Neurological and Communicative Diseases and Stroke/Alzheimer's Disease and Related Disorders Association |
| NINDB | National Institute of Neurological Diseases and Blindness |
| NIOSH | National Institute for Occupational Safety and Health |