- monotony: A lack of variety.
- monsieur: A French title of respect, equivalent to Mr. and sir.
- monstrosity: Anything unnaturally huge or distorted.
- moonbeam: A ray of moonlight.
- morale: A state of mind with reference to confidence, courage, zeal, and the like.
- moralist: A writer on ethics.
- morality: Virtue.
- moralize: To render virtuous.
- moratorium: An emergency legislation authorizing a government suspend some action temporarily.
- morbid: Caused by or denoting a diseased or unsound condition of body or mind.
- mordacious: Biting or giving to biting.
- mordant: Biting.
- moribund: On the point of dying.
- morose: Gloomy.
- morphology: the science of organic forms.
- motley: Composed of heterogeneous or inharmonious elements.
- motto: An expressive word or pithy sentence enunciating some guiding rule of life, or faith.
- mountaineer: One who travels among or climbs mountains for pleasure or exercise.
- mountainous: Full of or abounding in mountains.
- mouthful: As much as can be or is usually put into the or exercise.
- muddle: To confuse or becloud, especially with or as with drink.
- muffle: To deaden the sound of, as by wraps.
- mulatto: The offspring of a white person and a black person.
- muleteer: A mule-driver.
- multiform: Having many shapes, or appearances.
- multiplicity: the condition of being manifold or very various.
- mundane: Worldly, as opposed to spiritual or celestial.
- municipal: Of or pertaining to a town or city, or to its corporate or local government.
- municipality: A district enjoying municipal government.
- munificence: A giving characterized by generous motives and extraordinary liberality.
- munificent: Extraordinarily generous.
- muster: An assemblage or review of troops for parade or inspection, or for numbering off.
- mutation: The act or process of change.
- mutilate: To disfigure.
- mutiny: Rebellion against lawful or constituted authority.
- myriad: A vast indefinite number.
- mystic: One who professes direct divine illumination, or relies upon meditation to acquire truth.
- mystification: The act of artfully perplexing.
- myth: A fictitious narrative presented as historical, but without any basis of fact.
- mythology: The whole body of legends cherished by a race concerning gods and heroes.
- nameless: Having no fame or reputation.
- naphtha: A light, colorless, volatile, inflammable oil used as a solvent, as in manufacture of paints.
- Narcissus: The son of the Athenian river-god Cephisus, fabled to have fallen in love with his reflection.
- narrate: To tell a story.
- narration: The act of recounting the particulars of an event in the order of time or occurrence.
- narrative: An orderly continuous account of the successive particulars of an event.
- narrator: One who narrates anything.
- narrow-minded: Characterized by illiberal views or sentiments.
- nasal: Pertaining to the nose.
- natal: Pertaining to one's birth.