Replace Multiselect fields

Replace Multiselect fields

Is there a way to "replace" / "rename" a Multiselect Field, so existing records will reflect this update? eg. we created a Field once called "Festival Tickets", but now want to just use "Festivals". How can we ensure all records who had "Festival Tickets" in the past will now be updated to "Festivals" for this field? There are hundreds of them so a manual update wouldn't really work.