WordNet sense 1 (a large sandwich made of a long crusty roll split lengthwise and filled with meats and cheese (and tomato and onion and lettuce and condiments); different names are used in different sections of the United States):

bomber, hero, hoagie, hoagy, sub, submarine, torpedo, wedge, zep, Cuban sandwich, hero sandwich, Italian sandwich, submarine sandwich

WordNet sense 2 (grinding tooth with a broad crown; located behind the premolars):

molar

WordNet sense 3 (machinery that processes materials by grinding or crushing):

mill, milling machinery