| MA | Master of Arts |
| Maj | Major |
| MArch | Master of Architecture |
| MB | Bachelor of Medicine |
| MBA | Master of Business Administration |
| MBE | Member of the Order of the British Empire |
| MC | Military Cross |
| MD | Doctor of Medicine |
| ME | Master of Engineering |
| MEd | Master of Education |
| MEE | Master of Electrical Engineering |
| memb | member |
| mfr | manufacturer |
| mi | mile(s) |
| Mily | Military |
| Min | Minister |
| MIT | Massachusetts Institute of Technology |
| Mlle | Mademoiselle |
| MP | Member of Parliament |
| MPH | Master of Public Health |
| MS | Master of Surgery; Master of Science |
| MSciMed | Master of Scientific Medicine |
| MVO | Member of the Royal Victorian Order |