Show hand to stop the car.

[tufguy]

Do we "Show our hand to stop a car on the road" or do we "Extend our hand to signal the driver to stop the car"?

 

[tedmc]

hand-signal the driver to stop
give hand signal for the driver to stop

 

[emsr2d2]

hand-signal the driver to stop
give hand signal for the driver to stop

Neither of those is natural. Giving a hand signal is associated with cyclists, or with cars whose indicators aren't working.

 

[emsr2d2]

To hail a car on the road.

"Hail" is a gesture in order to stop it.

In BrE, you would only hail a cab (we also use "flag down"). It doesn't work for stopping a normal car on the road. If, for example, there were an accident ahead and you were trying to stop the traffic coming up behind it, there wouldn't be a standard verb for it. I might say "I stood in the road and frantically waved my arms to stop the oncoming cars".

 

[Tdol]

A police officer could hold their hand up to stop a car.

 

[tufguy]

In BrE, you would only hail a cab (we also use "flag down"). It doesn't work for stopping a normal car on the road. If, for example, there were an accident ahead and you were trying to stop the traffic coming up behind it, there wouldn't be a standard verb for it. I might say "I stood in the road and frantically waved my arms to stop the oncoming cars".

If a someone is in stranded on an abandoned road because of their broken down car and wants a car to stop that is passing by then what do we need to say? "They waved their hand to stop the car".

 

[GoesStation]

They waved down a passing car.

 

[emsr2d2]

They waved down a passing car.

Or flagged down a passing car.

As far as what police/traffic officers do, I'd say "The officer put/held his/her hand up to stop the traffic".

 

[GoesStation]

Not long after I arrived in Toronto, Ontario, Canada, I was a little surprised to see a policeman pointing at the road as I passed him. I didn't think about it much at the time and just drove on, wondering a bit why he'd done that.

Eventually I noticed that in Ontario, pointing at the road is the gesture the police use to tell a driver to pull over. They're far too polite to do anything more demonstrative. I probably avoided a speeding ticket that day.

 

[SoothingDave]

He just pointed to the road? I would expect a sweeping gesture to the side, to indicate that you should pull over.

 

[GoodTaste]

He just pointed to the road? I would expect a sweeping gesture to the side, to indicate that you should pull over.

Sounds like you are a traffic police? The purpose of stopping the car decides the context and what gesture you should use.

 

[GoesStation]

He just pointed to the road? I would expect a sweeping gesture to the side, to indicate that you should pull over.

You and I are Americans. In Ontario, that would be far too dramatic. By way of comparison, here's what a Canadian "DO NOT ENTER" sign looks like:

 

[GoesStation]

The purpose of stopping the car decides the context and what gesture you should use.

I think I reacted the same way most Americans would when I saw this: I looked at the officer, slowed down a bit, and drove by. An American cop would make dramatic gestures to convey the message "pull over, now!"