Related Clues:
- They are engaged in making machines work
- Gear components
- Teeth on the edge of a wheel
- Rotating machine parts
- Nanny __: security devices
- Vital elements
- Bit players in a big machine
- Some working parts
- They aren't major players
- Lettuce sandwiches good for teeth
- Home security devices, for short
- Gear elements
- Parts of the machinery on the margins of computer bugs
- Gear sprockets
- Essentials of an industrial revolution?