pull leg

pull someone's leg
or leg pulling

Meaning:

• tease someone
• joking around
• deceive in a playful, harmless way
• fool or trick someone in a humorous way

Example:

1. Don't worry about what he said. He's just pulling your leg.
2. You can't be serious about that! Stop pulling my leg.
3. Did he mean it when he said he's leaving you or was he just pulling your leg?
4. As a big brother, he was always pulling his sister's leg, but he was there for her when needed.
5. I think he was just pulling your leg when he said you've failed in the exam.
6. I was just pulling your leg when I said that the company is going to shut down.

Origin:
The phrase first appeared in the late 1800s in America. The origin is not clear, though there are two popular theories, but both implausible. The first theory says that thieves used to pull the legs of their victims to put them off guard, so that they could rob them. The second one refers to hangings that were held in Tyburn, England. It is said that people were hired to hang on the victim's leg to give them a quick execution.