- 1 Mary, Blessed Virgin, Saint - Presentation
- 1 Mary, Blessed Virgin, Saint - Purification
- 7 Mary, Blessed Virgin, Saint - Queenship
- 1 Mary, Blessed Virgin, Saint - Symbols
- 12 Mary, Blessed Virgin, Saint - Visitation
- 4 Mary, of Bethany, Saint
- 97 Maryland
- 7 Maryland State Building
- 2 Mascher Street
- 1 Masjids
- 1 Masks
- 1 Masland Dura Leather Factory
- 1 Masland, C.H. & James Allegheny Avenue Dye Works
- 1 Mason & Co.
- 1 Mason & Hamlin Co.
- 1 Mason, Josiah, 1795-1881
- 17 Masonic buildings
- 6 Masonic Hall
- 35 Masonic Temple
- 4 Masonry
- 1 Mason's Blacking Factory
- 1 Masquerades
- 66 Mass transit
- 51 Massachusetts
- 14 Massachusetts State Building
- 9 Massacre of the Holy Innocents
- 1 Massacres
- 2 Masses (eucharists)
- 1 Massett, Stephen C.
- 8 Master Humphrey's Clock
- 11 Master Street
- 1 Master Street
- 1 Masters
- 1 Mastodons
- 2 Masts
- 3 Matches
- 5 Maternity hospitals
- 1 Mathematical instruments
- 1 Mathematics
- 1 Mathew, Theobold 1790-1856