I am not sure if there were Halloween decorations in the year 1515, but if there were, they very well could have featured the word boo.
Boo, and the variations “bo” or “boh,” date back to around 500 years ago. The word is of Scottish origin but some trace it to a Greek word that meant “to cry aloud, roar or shout.”
In the 18th century, booing began being used as a sound of displeasure, as Italian opera fans were often called boo birds when they did not enjoy a show. According to linguists, the word is such a great word to show discontent “because ‘ooh’ or ‘oh’ sounds can be pronounced at a higher volume than other vowel sounds, such as the ‘ee’ in ‘wheel.’ Since boo is a monosyllable, it can also be said very quickly, which may add to its scariness.”
So let’s recap…the word boo is based on a Greek word that means to roar & it is easy to say loudly and at a rapid pace. A loud & fast road. Seems like the perfect scary word for Halloween.
But not everyone agrees. In Spain, they say “uuh” to scare somebody. In France it’s “hou” and in Czech it’s “baf.”