- m ... M42
- M44 ... maat
- Maathai, Wangari ... macaroni wheat
- macaronic ... MacDonald, James Ramsay
- MacDonald, Jeanette ... Mach cone
- Mach number ... Machkund Lake
- Machkund River ... Mackinac Bridge
- Mackinac Island ... Macon, Nathaniel
- Maçon, Robert Le ... Macropus rufogriseus
- Macropus rufus ... Madama, Palazzo
- madambo ... mader
- Madera Volcano ... Madman of Piney Woods, The
- Madman or Saint ... Madrid train bombings of 2004
- Madrid, Battle of ... Maéwo
- Maeztu y Whitney, Ramiro de ... Magenta
- magenta ... Magill, Helen
- Magill, Juliette Augusta ... magnetic induction
- magnetic intensity ... Magnificent Magyars
- Magnificent Matador, The ... magokoro
- Magon ... Mahalanobis, P.C.
- Mahalanobis, Prasanta Chandra ... Mahdī, Sayyid ʿAbd al-Raḥmān al-
- Mahdia ... Mahon Tribunal
- Mahon, Derek ... Maiko wa redî
- Maikop ... Maines, Natalie Louise
- mainframe ... Máj
- Máj ... Major, cathedral of la
- Major, John ... Makepeace Experiment, The
- maker ... Makushin
- Makutu ... Malanga, Christian
- Malange ... Malbodius, Jan
- Malbone, Edward Greene ... Malerba, Luigi
- Malerei, Photografie, Film ... Malina, Judith
- Malinche ... Malmesbury
- Malmesbury Abbey ... Maltese Falcon, The
- Maltese Falcon, The ... Mama Told Me Not to Come
- Mama Weed ... Mamoudzou
- Mamoulian, Rouben ... Man of the Crowd, The
- Man of the People, A ... man-eater
- man-eater ... Manche
- Manche, La ... mandarin
- Mandarin language ... Mands Himmerig
- Mandsaur ... Manger, Itzik
- Mangerton ... manière criblée
- manière noire ... Manitoba Schools Question
- Manitoba, flag of ... Mannes, Marya
- Mannesmann AG ... Mansfield, Mount
- Mansfield, Richard ... mantle
- mantle ... Manufacturing Belt
- Manufacturing Consent: The Political Economy of the Mass Media ... Māori Boy: A Memoir of Childhood
- Māori hen ... Maquiritare
- maquis ... Marathi literature
- marathon ... Marcellinus, St.
- Marcello, Benedetto ... Marchi, Emilio De
- Marchiafava-Bignami disease ... Mardin
- Mardin ... Margaret of Scotland, St
- Margaret of Tirol ... Marguerite de Provence
- Marguerite de Valois ... Marianus Scotus
- Marianus Scotus ... Marimbondo Falls
- Marimda Banī Salāma ... Marīnid dynasty
- Marinin, Maksim ... Mariy-El
- Mariyah, al- ... marketing expense-to-sales analysis
- marketing facilitator ... Marmes Rock Shelter
- Marmion ... Marquette
- Marquette ... Mars
- Mars Advanced Radar for Subsurface and Ionosphere Sounding ... Marsh, William Wallace
- marshal ... Marteau sans maître, Le
- Martel ... Martin Salander
- Martin system ... Martínez de Perón, María Estela
- Martínez Estrada, Ezequiel ... Maru
- Marua ... Mary of Modena
- Mary Of Orange ... Masaniello
- Masanori Murakami ... Masjed-e Emām
- Masjed-e Jāmeʿ-e Eṣfahān ... Mason, Lowell
- Mason, Luther Whiting ... mass-energy
- mass-energy equation ... massively parallel processing computer
- Masson, André ... Masterson, Bartholomew
- Masterson, Bat ... Matale
- Matalin, Mary ... maternal mortality
- maternal school ... Mathijs, Jan
- Mathilde ... Matricaria chamomilla
- matrilineage ... Matteo di Cione
- Matteo il Grande ... Maturana, Humberto
- maturation ... Maumee River
- Maumee, Lake ... Mauser, Peter Paul
- Mausoleum ... Maxim, Hiram
- Maxim, Hiram Percy ... May Organization
- May Pen ... Mayer, Lazar
- Mayer, Louis B. ... Mayr, Ernst
- Mayr, Ernst Walter ... Mažuranić, Ivan
- mazurek ... Mbwila, Battle of
- Mc ... McCarthy, Tom
- McCarthyism ... McCracken, Robert
- McCracken, Voros ... McEwan, Ian Russell
- McEwen, Douglas ... MCHR
- McHugh, James Francis ... McLaughlin, Sara Agnes
- McLaurin v. Oklahoma State Regents for Higher Education ... McNutt, Marcia
- McNutt, Marcia Kemper ... Mead, James I.
- Mead, Joseph ... Meany, George
- Meara, Anne ... mechanical isolation
- mechanical manipulator ... Médard of Noyon, Saint
- Medawar, Sir Peter B. ... medical corps
- Medical Council of Canada ... Medicine Lodge River
- Medicine Lodge, Treaty of ... Mediterranean spurge
- Mediterranean stone pine ... Meerwein, Hans
- Mees, C. E. Kenneth ... Megalops cyprinoides
- megalopsyche ... Mehmed
- Mehmed ... Meine Nachforschungen über den Gang der Natur in der Entwicklung des Menschengeschlechts
- Meine Verse ... Mekons, the
- Mekrān ... Melbourne Cricket Ground
- Melbourne Cup ... Melittidae
- Melittophagus pusillus ... Melpomene
- Melqart ... Memnon
- Memnon ... Memories of My Exile
- Memories of My Life ... Mena, Juan de
- Mena, Pedro de ... Mendieta, Ana
- Mendieta, Ana Maria ... Menifee
- Menil Collection ... Menschenwee
- Menschliches, Allzumenschliches ... MEP
- mepacrine ... Merchandise Mart
- Merchandise Mart Hall of Fame ... mercury(II) chloride
- mercury(II) oxide ... Meridiani Planum
- Meridional Carpathians ... meromictic lake
- meromixis ... Mersenne, Marin
- Mersey Beat ... mesencephalic tegmentum
- mesencephalon ... Mesoplodon peruvianus
- Mesopotamia ... Messerschmitt 109
- Messerschmitt AG ... metacarpal
- metacarpus ... metameric segmentation
- metamerism ... metazoonosis
- Metcalf, Laura Elizabeth ... methemoglobin
- methemoglobinemia ... methylenedioxyamphetamine
- methylidyne ... Metropolitan Sacristy
- Metropolitan Stadium ... Mexican hairless
- Mexican hallucinogenic mushroom ... Meyer, O. E.
- Meyer, Paul ... mho
- Mhondora ... Michael Borisovich
- Michael Bublé ... Michelsen, Christian
- Michelsen, Peter Christian Hersleb Kjerschow ... microbenthos
- microbial genetics ... Microhydromys richardsoni
- Microhylidae ... microsporangium
- microspore ... midbrain
- midcarpal joint ... middle Ural tradition
- Middle Veld ... midlatitude cyclone
- midlatitude jet stream ... Miercurea-Ciuc
- Mieres ... Miguel
- Miguel, Edward ... Mil Mi-12
- Mil Mi-24 Hind ... Milēsiaka
- Milesian tale ... military rule
- military science ... mille passus
- Mille, Cecil B. de ... Miller, Maria
- Miller, Marilyn ... millipede
- millisecond delay cap ... Milton Hershey School
- Milton Keynes ... Min Jiang
- Min kamp ... Mind That Found Itself, A
- Mind’s Eye, The ... Minerva
- MINERVA ... Minidoka Relocation Center
- Minié ball ... Minnan language
- Minneapolis ... minority carrier injection
- minority education ... Minyas
- Minyue ... Mirage
- Mirage ... mirror drawing
- Mirror for Magistrates, A ... Misére de la Philosophie
- Miserere ... Miss Lulu Bett
- Miss MacIntosh, My Darling ... Missionaries of Charity, Order of the
- Missionaries of the Sacred Heart of Jesus ... Mister Buddwing
- Mister Ed ... Mitchell, Maria
- Mitchell, Millard ... mitral valve
- Mitrany, David ... Mixed Doubles: An Entertainment on Marriage
- mixed economy ... mizzenmast
- mizzonite ... Mnogo li cheloveku zemli nuzhno?
- Mnong ... Mobius the Stripper
- Möbius, August Ferdinand ... Modalistic Monarchianism
- Modalité du jugement, La ... modern legend
- modern logic ... Modisane, William
- modism ... Moghul carpet
- Mogi das Cruzes ... Möhler, Johann Adam
- Mohmand, Abdul Ahad ... Moksobomyo
- Moku Manu ... molecular cloud
- molecular computer ... molly
- Molly Hatchet ... Mommie Dearest
- Mommie Dearest ... Monastral Fast Blue G
- monatomic gas ... money laundering
- Money Laundering and Financial Crimes Strategy Act ... Monilinia
- monilophyte ... Monnow Bridge
- Monnoyer, Jean-Baptiste ... monometallism
- monometer ... Monroe, Jay
- Monroe, Marilyn ... Mont des genêts, Le
- Mont Jacques-Cartier ... Montazeri, Hossein Ali
- Montazeri, Hossein-Ali ... Montes the Matador and Other Stories
- Montes, Ismael ... Montiel, Battle of
- Montigny, A. H. V. Grand Jean de ... Monument to the Third International
- Monument, The ... Moon, secular acceleration of the
- Moon, Sun Myung ... Moore, Dudley Stuart John
- Moore, Ely ... Mora, José de
- Mora, Pat ... Morante, Elsa
- Morat, Battle of ... Morecambe Bay
- Moree ... Morgan, Frederick Edgeworth
- Morgan, Garrett ... Morinus, Joannes
- Morioka ... Moro
- Moro ... Morris
- Morris ... Morristown
- Morristown National Historical Park ... Morton H. Meyerson Symphony Center
- Morton National Park ... Moscoso de Gruber, Mireya Elisa
- Moscoso, Luis de ... Moshesh
- Moshfegh, Ottessa ... Most Famous History of the Seaven Champions of Christendome, The
- Most Holy Redeemer, Congregation of the ... Mother’s Day
- Mother’s Day ... motmot
- moto ... mottled spurge
- motto ... Mount Holyoke Seminary and College
- Mount Hood National Forest ... mountain goat
- mountain gorilla ... Mouroir: Mirrornotes of a Novel
- Mouron, Adolphe-Jean-Marie ... Movement for Multiparty Democracy
- Movement for National Renewal ... Moxeke
- moxibustion ... MPAJA
- Mpande ... Mr. Nobody
- Mr. Noon ... MS-DOS
- MS. Found in a Bottle ... mubālaghah
- Mubārak Nāgawrī, Shaykh ... Muddy River Hamlet
- müde Tod, Der ... Mugia, Deo
- Mugil cephalus ... Muḥammad Ture
- Muḥammad Turée ... Mujuru, Joice
- Mukacheve ... Mules and Men
- muleta ... Mulliken, Robert Sanderson
- Mullin, Chris ... multiple endocrine neoplasia type 2B
- multiple epiphyseal dysplasia ... mumble the peg
- mumblecore ... Mundinus
- Mundipharma ... Muñoz, Anthony
- Muñoz, Fabricio Alvarado ... mura
- Mura ... Murder Most Horrid: The Grisliest Deaths of Roman Catholic Saints
- Murder Mystery ... Murmuring Judges
- Murna River ... Murray, John
- Murray, John ... Musa
- Musa ... muscular atrophy
- Muscular Christianity ... Musgrave, Thea
- Musgraves, Kacey ... Música + alma + sexo
- Musica Britannica ... muskmelon
- Muskogean languages ... mustard gas
- mustard oil ... Mutloatse, Mothobi
- Mutlu, Halil ... Muʿizz al-Dawlah
- Muʿizz al-Dīn Muḥammad ibn Sām ... My Double Life: Memoirs of Sarah Bernhardt
- My Dream of Martin Luther ... My Own Private Idaho
- My Own Two Feet ... Myconius, Oswald
- mycophenolate mofetil ... Mymaridae
- Mymensingh ... Myrica californica
- Myrica cerifera ... Mysterious Object at Noon
- Mysterium ... Myxiniformes
- Myxobolus pfeifferi ... Mʾzabite
