The difference between vacation and holiday is not all that great.
Vacation is an American term and is used for when someone goes to another place for a break.
Holiday is used in both American and British English.
American – A holiday is a time of year when people are celebrating a festival, usually religious. That’s why when Christmas comes, Americans say Happy Holidays!
British – A holiday is the same as when Americans say vacation. In British English, if you say have a good holiday it means that people are going to travel to another place for a break. However, in British English if there is day off from work during the year, it is also known as a holiday.
This is the same in American English too.
Recommended for you:
Vacation – Improve Your Vocabulary [Infographic]
Travel, Holiday, Vacation Vocabulary and Dialogs in English
Travel English Vocabulary with James [Video]
10 New Year Wishes and Useful Expressions