In the UK we'd talking about "going on holiday" whereas I understand US usage to be "going on vacation", with talk about a "holiday" being more in line with the UK's "public holiday" concept.
My chat response on this was:
From a usage perspective, for here, probably. The meanings aren't always the same as, for example, Christmas is a holiday, but not necessarily a vacation. Nevertheless, I think for our purposes the UK usage of holiday as a vacation is probably a reasonable synonym.
I think the synonym would be good to clear up any confusion between going on a holiday/vacation, and holidays such as days of celebration.
The only question I can think of where a holiday tag might be used is if it's something like dealing with a cat and a christmas tree. But the question is about the animal not the holiday so it doesn't really matter.