"Um, Mom, what's a Scurvy Pirate?"
"Well, Scurvy was a disease that, a long time ago, often effected people who worked on boats and spent long amounts of time a sea. They were on the ocean for long periods of time without fresh fruits and vegetables and Scurvy is a disease caused by lack of vitamin C, which is in alot of fruits and vegetables. Pirates were often at sea for long periods of time and didn't have proper nutrition so they often got Scurvy. That's how you get the term Scurvy Pirate. Now days you can get oranges or tomatoes at the store so it happens much less. Does that make sense?"
"Yeah...(long pause................) Pirates got sick cause their Mommies didn't make them take their vitamins."