Take the bit between your teeth
Meaning
Take decisive and energetic action.
Usage
Used to describe a determined shift in attitude.
Origin & History
Origins and dates here are approximate summaries. Many idioms have disputed or unknown origins, and not every date has been checked against a historical dictionary, so treat specific dates and stories as a starting point rather than a citation.
Horse training image of a horse grasping the bit and charging ahead.
Recorded in English since the 16th century.