The Centers for Disease Control keeps exhaustive records detailing how Americans die. It's morbid and fascinating.

The top killers aren't surprising — cancer, heart disease, and other familiar causes of death are all up there.

But scroll further down, and some strange things start to appear, including several sub-categories devoted to deaths related to three wheeled motorcycles. The list tells us a great deal about the ways we describe and categorize death, sometimes with hyper-specificity and other times with puzzling vagueness.

We put together a list of some of the most unusual causes of death (complete with their codes used in the database and their toll between 1999 and 2014) that are still surprisingly common. While extremely rare, these are not the one-time occurrences you might expect — they've claimed thousands of lives. Most bring up more questions that answers.