Marc - McCl
- Marconi
- Marconi , Marchese Guglielmo
- Marconi's
- Marcus , Rudolph Arthur
- Margulis , Lynn
- Marignac , Jean Charles Galissard de
- Marignac, Jean Charles Galissard de
- Mariotte , Edmé
- Markov , Andrey Andreyevich
- Martin , Archer John Porter
- Martin, Archer John Porter
- Maskelyne , Nevil
- Mather , Kenneth
- Matthews
- Matthews , Drummond Hoyle
- Matthias , Bernd Teo
- Matuyama , Motonori
- Maunder , Edward Walter
- Maupertuis
- Maupertuis , Pierre-Louis Moreau de
- Maury , Antonia Caetana de Paiva Pereira
- Maury , Matthew Fontaine
- Maxwell
- Maxwell , James Clerk
- Mayer
- Mayer , Julius Robert von
- Maynard Smith , John
- Mayow , John
