The medical term for a fart is “flatulence,” which is defined as “flatus expelled through the anus.” Flatus is strictly defined as gas produced during digestion—generally in the stomach and/or gut. Through this book Dani and Nick are taking part in flatology, or the study of flatulence, even though their main area of expertise is not in this field.
The word “fart” dates back to the fourteenth century, before the term flatulence came into use, and was used specifically to mean breaking wind loudly. Today the term fart is more commonly used to describe any gas expelled from the end of an animal that is opposite to its mouth—whether this be through the anus, cloaca or a specialized duct—and if it is audible or not. This, therefore, is the definition used throughout this book. So, although some of the farts in this book may not fit the strict medical definition of flatulence, they would generally be accepted as a fart to any human encountering them.