To turn on a dime

To turn on a dime means:
To turn very quickly and with great agility, as in a car that can turn on a dime, even at high speeds.
To change focus, activity, opinion, or behavior very suddenly or abruptly.
The phrase can also refer to the ability of an automobile to stop, turn, or maneuver in a small space.

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The phrase "turn on a dime" means to change direction very quickly and precisely, often in a tight space. The origin of the phrase can be traced back to the early 20th century in the United States.

During this time, the phrase "turn on a sixpence" was commonly used in England to describe a similar maneuver. In the United States, the phrase was adapted to "turn on a dime," likely due to the fact that dimes were smaller and had a tighter turning radius than sixpence coins.

The phrase was originally used in reference to the maneuverability of ships and aircraft. In the 1920s and 1930s, it became a popular idiom used to describe any situation where a quick change of direction was necessary, such as in sports or driving.

Today, the phrase "turn on a dime" is still commonly used in everyday conversation and is often used figuratively to describe a person's ability to change course or adapt quickly in response to changing circumstances. It has become a popular way to express the idea of agility and flexibility, both in a physical and metaphorical sense.