| macaroni | machine shop | magazine distributors |
| mail-order houses | maker industrial | malt beverages |
| management consulting services | manufacturers agents | manufacturers representatives |
| manufacturing industries | marble | marble products manufacturers |
| marble products natural | marina | marine cargo handling |
| marine contractors | marine designers | marine fats |
| marine insurance | marking devices | martial arts schools |
| masonry contractors | massage school | mattress manufacturers |
| meat market | meat products | meats |
| meat wholesale | mechanical power transmission equipment | mechanical power transmission equipment manufacturers |
| medical clinic | medical dental assistant technician schools | medical instruments |
| medical laboratories | membership organizations | membership sports |
| men's clothing retail | men clothing | men coats |
| mens clothing stores | men suits | mental health clinics |
| merchandising machine operators | metal coating | metal cutting type |
| metal doors | metal finishing | metal goods |
| metal goods manufacturers | metal polishing | metal service centers |
| metals service offices | metal stamping | metal stamping manufacturers |
| mexican restaurant | middle school | millwork |
| millwork contractors | millwork manufacturers | mineral conservation |
| mini bike dealers | mini bikes | mining machinery |
| miscellaneous accessory stores | miscellaneous apparel stores | miscellaneous business credit institutions |
| miscellaneous commercial sectors | miscellaneous food stores | miscellaneous general merchandise stores |
| miscellaneous homefurnishings | miscellaneous personal service | miscellaneous publishing |
| miscellaneous retail stores | mobile home community | mobile home dealers |
| mobile home parks | mobile homes | molder |
| monetary policy | monorail | montessori school |
| mortgage banker | mossaic work | motel |
| motion picture equipment | motion picture film distributions | motion picture film exchanges |
| motion pictures | motion picture supplies | motion picture theaters |
| motorcycle | motorcycle dealers | motor home |
| motor scooter dealers | motor scooters | motor vehicle |
| motor vehicle new parts | motor vehicle parts | motor vehicle supplies |
| movie theaters | moving supplies | moving supplies renting |
| muffins | mufflers engine | museum |
| musical instruments | musical instrument stores | music school |
