| Term | Definition |
| m | minim |
| MA | medical assistant |
| Mat | maternity |
| mcg | microgram |
| MD | medical doctor |
| MD | muscular dystrophy |
| MD | myocardial disease |
| Med | medical, medicine |
| mEq | milliequivilent |
| mg | milligram |
| Mg | magnesium |
| MI | myocardial infarction |
| MICU | medical intensive care unit |
| min | minute |
| ml | milliliter |
| MLT | medical laboratory technician |
| mm | millimeter |
| MN | midnight |
| mod | moderate |
| MOM | milk of magnesia |
| MRI | magnetic resonance imaging |
| MS | muscular skeletal |
| MS | mitral stenosis |
| MS | multiple sclerosis |
| MT | medical technician |
| N | nitrogen |
| N/A | not applicable |
| Na | sodium |
| NA | nurse assistant |
| NaCl | soduim chloride |
| NB | newborn |
| N/C | no complaints |
| neg | negative |
| Neur | neurology |
| NGT | nasal gastric tube |
| NICU | neonatal, neurological intensive care unit |
| NIDDM | noninsulin dependent diabetes mellitus |
| NIH | National Institutes of Health |
| NKA | no know allergies |
| NKDA | no known drug allergies |
| no | none |
| NO | nursing office |
| noct | at night |
| NP | nurse practitioner |
| NPO | nothing by mouth |
| NS | normal saline |
| Nsy | nursery |
| N&V | nausea & vomiting |
| NVD | nausea vomiting diarrhea |
| NVS | neurological vital signs |