get the bit in one's teeth

noun

1. the part of a bridle that goes into a horse's mouth, used to control the horse
2. anything that curbs or controls
3. the part of a pipestem held in the mouth
4. the part of a key that actually turns the lock
5. the cutting part of any tool, as the blade of a plane
6. a drilling or boring tool for use in a brace, drill press, etc.

transitive verb bitted, bitting

1. 1. to put a bit into the mouth of (a horse)
   2. to train to the bit
2. to check or curb
3. to make the bit on (a key)