The word ball in ballroom can be separated but it is not really a synonym for dance. A ball is an old fashioned term. It is like a large gathering of people where they will be dancing and it is a formal gathering. You can't really use it in place of dance. Sometimes I go dancing and I would like to try ballroom dancing.

Hi Mr.Andre,you're right.However,we can't understand this word by dividing it into different parts. "ballroom" means "a large room for dancing'' or "dance room" P/s:It's "synonym",not"synonimo"(I know this italian word means "sinonym"in english,right?:)

In the "olden days", like 90 years ago and earlier, people would get dressed up in fancy clothes and go to the "ball". That meant a big fancy formal dance in a large formal room with chandeliers and ladies in beautiful full gowns and men in suits. It was a type of a planned Dance that was meant for rich people, because poor people in the countryside had different types of dancing....probably in barns, with country musical instruments made out of wash tubs and fiddles they enjoyed. When someone planned a "Ball" and invited people to come to the dance, they would have ballroom dancing. Just doing a dance did not mean you were doing a "ball". It is not a synonym.

I used to go to Salsa lessons. :)