Spill the beans

 

“To reveal a secret” is the most popular meaning of “spill the beans.” The phrase comes from the ancient Greeks, among whom beans were very important not only for food but also in the conduct of their local elections.

When a Greek voted, his ballot was cast by putting a bean in the helmet of the candidate of his choice whose helmet lay alongside those of the whole slate of candidates.  The candidate whose helmet had the greatest number of beans in it at the close of the election was declared the winner.The count was public and when the winner was announced, his helmet, with the beans in it, was returned to him. Then he would “spill the beans” out of the helmet and in the middle of the applause of the voters, put it on his head.  

This act symbolized his acceptance of the office in which he had been elected.  Because the helmet contained the outcome of the election,” spill the beans” became synonymous with disclosing a secret which is the way we use the phrase today.