take the bit between (one's) teeth

take the bit between (one's) teeth

To begin to do something with decisive, stubborn resolve; to act in an bullheaded and unruly manner. A reference to a horse that is no longer under the rider's control because the bit (part of the apparatus used to guide it) is out of place in its mouth. The CEO started ignoring the board's demands and took the bit between her teeth, running the company the way she saw fit. In spite of my counsel, my clients took the bit in their teeth and went public with their accusations.
See also: between, bit, take, teeth
Farlex Dictionary of Idioms.

get/take the bit between your ˈteeth

(informal) start doing something in a determined and enthusiastic way: Once he gets the bit between his teeth in an argument, no one can stop him.If the horse learns to hold the bit (see previous note) between its teeth, it can no longer be controlled by the rider.
See also: between, bit, get, take, teeth
Farlex Partner Idioms Dictionary
See also:
  • take the bit between the teeth
  • take the bit between the teeth, to
  • wild out
  • to the backbone
  • to the marrow
  • out of hand
  • get out of control
  • to (one's) bootstraps
  • to your bootstraps
  • amok