| m. | masculine |
| Macc. | (in the Apocrypha) Maccabees |
| Mach. | machinery, machine(s) |
| Mag. | magazine |
| Magn. | magnetism, magnetic |
| Mal. | (in the Bible) Malachi |
| Man. | manual |
| Managem. | management |
| Manch. | Manchester |
| Manip. | manipulation |
| Manuf. | manufacturing, manufacture(s) |
| Mar. | March |
| masc. | masculine |
| Mass. | Massachussets |
| Math. | mathematics, mathematical |
| Matt. | (in the Bible) Matthew |
| Meas. | measure |
| Measurem. | measurement |
| Mech. | mechanics, mechanical |
| med. | medieval |
| Med. | medicine, medical |
| Medit. | meditation |
| Mem. | memoir(s) |
| Merc. | mercury |
| Merch. | merchant(s) |
| Metall. | metallurgy |
| Metallif. | metalliferous |
| Metallogr. | metallography, metallographic(al) |
| Metallogr. | metallography |
| Metamorph. | metamorphosis |
| Metaph. | metaphysics |
| metaphor. | metaphorical(ly) |
| Meteorol. | meteorology, meteorologic(al) |
| Meth. | method(s) |
| metr. gr. | metri gratia |
| Metrop. | metropolitan, metropolis |
| Mex. | Mexican |
| Mic. | (in the Bible) Micah |
| Mich. | Michigan |
| Microbiol. | microbiology |
| Microsc. | microscopic(al) |
| midl. | midland(s) (dialect) |
| Mil. | military |
| Milit. | military |
| Min. | mineralogy |
| Mineral. | mineralogy, minaralogic(al) |
| Misc. | miscellaneous, miscellany |
| Miscell. | miscellany |
| mispr. | misprinted |
| mod. | modern |
| Mod. | modern |
| Monum. | monument |
| Morphol. | morphology |
| MS. | manuscript |
| MSS. | manuscripts |
| Mt. | mount(ain) |
| Mtg. | meeting |
| Mts. | mountains |
| Munic. | municipal |
| Munif. | munificence |
| Munim. | muniment |
| Mus. | music, musical |
| Mus. | museum |
| Myst. | mystery |
| Myth. | mythology |
| Mythol. | mythology |
