What is "tailgating"?

Dog, I've just spent 2 weeks in England (mostly Whitehaven) but I understand exactly your pain at the whole "different word usage" thing. I really didn't know much about rugby or cricket until I got over there. Rugby is my new favorite sport. But what's a scrum? Over here, that would be a small crumb. See? Tailgating is just what you said it was, following another car closely, but it is also cooking out and partying in the parking lot before a sporting event.