Origin of the Phrase

The exact origin of “pull someone’s leg” is debated, but there are two popular theories:

1. Criminal Origins (Mugging): One theory suggests that the phrase comes from old street crimes in 19th-century London. Thieves, known as “footpads,” would trip their victims by pulling on their legs, making it easier to rob them. Over time, this idea evolved from physically tripping someone to metaphorically tricking them for fun.
2. Theatrical or Fun Pranks: Another theory points to theater or early circus performances, where actors or clowns would pull each other’s legs for comedic effect. This playful act could have led to the meaning of tricking someone in a lighthearted way.

Both theories focus on the idea of causing someone to stumble, either physically or through a joke. However, today, the phrase is always used in a harmless, joking manner.