| Term | Definition |
| malignant | evil; deadly |
| malingerer | one who pretends to be sick to avoid work |
| malleable | capable of being changed; adaptable |
| malodorous | bad-smelling; stinking |
| mammoth | huge; enormous |
| manacle | handcuff; restraint |
| mandarin | influential person |
| mandate | an order; a command |
| mandatory | required; obligatory |
| mangle | to cut, slash, or crush so as to disfigure |
| mangy | shabby; filthy |
| manifest | evident; obvious |
| manifold | many; varied |
| manipulate | to handle or manage with skill; to influence a person in a bad way |
| manumit | to set free |
| maraud | to raid; to plunder |
| marital | warlike |
| martinet | a strict disciplinarian |
| martyr | one who suffers for a cause |
| marvel | to be amazed; to wonder |