- 1 Megaphones
- 6 Megargee Paper and Rags (Firm)
- 3 Melancholy
- 2 Melbourne, Australia
- 5 Mellon, Andrew W., 1855-1937
- 1 Melodeon
- 1 Melon Street
- 1 Melting
- 1 Melting ladles
- 29 Melville, Herman, 1819-1891
- 6 Members of Congress
- 1 Memoirs
- 2 Memorandums
- 2 Memorial arches
- 83 Memorial Hall
- 5 Memorials (monuments)
- 2 Memory
- 1 Memphis, Tennessee
- 787 Men
- 1 Mendelssohn-Bartholdy, Felix, 1809-1847
- 1 Mengs, Anton Raphael, 1728-1779
- 2 Menier (Firm : Paris)
- 2 Ménil-la-Tour, France
- 1 Meningitis
- 2 Mennonite
- 1 Mennonite churches
- 1 Menorahs
- 1 Menorca, Spain
- 1 Men's shirt industry
- 25 Mental institutions
- 3 Mental retardation
- 2 Mental states
- 2 Mentally handicapped children
- 4 Mentally ill persons
- 10 Menus
- 1 Menzies, Mr.
- 1 Mercantile Loan Association
- 7 Mercantile buildings
- 1 Mercantile Hotel
- 9 Mercantile Library of Philadelphia
