grinder

noun

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 Cuban sandwich hero hero sandwich hoagie hoagy Italian sandwich poor boy sub submarine submarine sandwich torpedo wedge zep
2.
grinding tooth with a broad crown; located behind the premolars
axle tooth cheek tooth grindtooth wangtooth molar
Derived from:
grind
3.
machinery that processes materials by grinding or crushing
mill milling machinery
Derived from:
grind
4.
a machine tool that polishes metal