What is spill the beans?

"Spill the beans" is an English idiom that means to reveal a secret or disclose information, often inadvertently or prematurely. The phrase is commonly used in casual conversation to indicate that someone has let slip details that were meant to be confidential or kept secret.

The origin of the phrase is somewhat unclear, although there are a few theories. One popular theory is that it might have originated from an ancient voting system in Greece, where people would cast their votes using beans. A spilled container of beans could reveal the results prematurely. However, this connection to voting in ancient Greece is more speculative than factual.

The phrase gained popularity in American English in the early 20th century, and it has since become a common expression in many English-speaking countries. It is often used in informal contexts and can be employed both humorously and seriously, depending on the situation.