1850 Atlas
| Name | What | Place | Pop | Other |
| Meredith | T | Belknap Co, NH | 3,521 | water by Winnipiseogee lake & river |
| Meredith | PT | Delaware Co, NY | 1,634 | water by Oleout creek & Susquehanna river |
| Meredith Centre | PO | Meredith twp, Belknap Co, NH | ||
| Meredith Mills | PO | Fulton Co, IN | ||
| Meredith Village | PV | Belknap Co, NH | water by Winnipiseogee lake | |
| Meredith's Tavern | PO | Monongalia Co, VA | ||
| Meredosia | V | Morgan Co, IL | water by Illinois river | |
| Meriden | PV | Sullivan Co, NH | ||
| Meriden | PT | New Haven Co, CT | 3,559 | water by Quinnupiac river |
| Meriden | PV | Mercer Co, IL | ||
| Meriden | PO | Cayuga Co, NY | ||
| Meriden Springs | PV | Hinds Co, MS | water by Bogue Chitto creek | |
| Meridenville | PV | Madison Co, AL | water by Flint river | |
| Meriomsburgh | OI | Monroe Co, PA | ||
| Merivale | PO | Montgomery Co, TN | ||
| Mermaid | PO | Newcastle Co, DE | ||
| Merom | PV | Sullivan Co, IN | water by Wabash river | |
| Merona | PO | McHenry Co, IL | ||
| Merrell | PO | Greene Co, GA | ||
| Merrick | PO | Queens Co, NY | ||
| Merrillsville | PO | Franklin twp, Franklin Co, NY | ||
| Merrilltown | PO | Travis Co, TX | ||
| Merrilville | PO | Lake Co, IN | ||
| Merrimack | T | Hillsborough Co, NH | 1,250 | water by Merrimack & Souhegan rivers |
| Merrimack | T | Franklin Co, MO | ||
| Merrimack | T | Jefferson Co, MO | ||
| Merrimack | T | St Louis Co, MO | ||
| Merriman | T | Crawford Co, MO | ||
| Merriman's Shop | PO | Prince Edward Co, VA | ||
| Merritt | PO | Barry Co, MI | ||
| Merritt's Bridge | PO | Lexington dist, SC | ||
| Merrittstown | PV | Luzerne twp, Fayette Co, PA | water by Dunlap's creek | |
| Merrittsville | PV | Greenville dist, SC | ||
| Merryall | PO | Bradford Co, PA | ||
| Merry Hill | PO | Bertie Co, NC | ||
| Merry Mount | PO | Warren Co, NC | ||
| Merry Oaks | PO | Barren Co, KY | ||
| Merry Oaks | PO | Hamilton Co, TN | ||
| Mershon's Cross Roads | PO | Laurel Co, KY | ||
| Merton | PO | Waukesha Co, WI | ||
| Mesopotamia | PT | Trumbull Co, OH | 959 | |
| Messina Springs | PO | Onondaga Co, NY | ||
| Messongo | PO | Accomac Co, VA | ||
| Meta | PV | Cass Co, IN | ||
| Metal | T | Franklin Co, PA | 1,221 | |
| Metamora | PO | Fulton Co, OH | ||
| Metamora | PO | Franklin Co, IN | ||
| Metamora | PT | Lapeer Co, MI | 821 | |
| Metamora | PO | Woodford Co, IL | ||
| Metamora | PO | Pike Co, IL | ||
| Metedeconk | PO | Ocean Co, NJ | ||
| Methuen | PT | Essex Co, MA | 2,538 | water by Merrimack & Spicket rivers |
| Metomen | PO | Fond du Lac Co, WI | ||
| Metompkin | PO | Accomac Co, VA | ||
| Metropolis City | PV | Johnson Co, IL | 1,215 | |
| Mets | PO | Steuben Co, IN | ||
| Metuchen | PV | Middlesex Co, NJ | ||
| Mexico | PT | Oxford Co, ME | 482 | water by Androscoggin river |
| Mexico | PT | Oswego Co, NY | 4,221 | water by Salmon creek & Lake Ontario |
| Mexico | PV | Juniata Co, PA | ||
| Mexico | PO | Tymochtee twp, Wyandott Co, OH | ||
| Mexico | PV, CH | Audrain Co, MO | seat of justice, water by Salt river | |
| Mexico | PO | Miami Co, IN | ||
| Mexico | PO | Jefferson Co, AL | ||
| Meyer's Mills | PO | Somerset Co, PA | ||
| Meyerstown | PV | Jackson twp, Lebanon Co, PA | ||
| Miami | PT | Hamilton Co, OH | 1,305 | water by Ohio & Wabash rivers |
| Miami | PV | Whitewater twp, Hamilton Co, OH | water by Miami river | |
| Miami | T | Clermont Co, OH | 2,690 | |
| Miami | T | Greene Co, OH | 1,865 | water by Little Miami river |
| Miami | T | Logan Co, OH | 775 | |
| Miami | T | Montgomery Co, OH | 3,456 | |
| Miami | PO | Dade Co, FL | ||
| Miami | PO | Saline Co, MO | ||
| Miami | PO | Miami Co, IN | ||
| Miamisburgh | PV | Miami twp, Montgomery Co, OH | water by Miami river & Miami canal | |
| Miamisville | PO | Clermont Co, OH | ||
| Mianus | PO | Fairfield Co, CT | ||
| Miatt | PT | Lawrence Co, OH | ||
| Micanopy | PO | Alachua Co, FL | ||
| Miccosukee | PO | Leon Co, FL | ||
| Michaelsville | PV | Harford Co, MD | ||
| Michigan City | PV | La Porte Co, IN | 1,002 | water by Lake Michigan & Trail creek |
| Michigantown | PV | Clinton Co, IN |