entrails
The inner organs of a body, especially the intestines.
Entrails are the internal organs of an animal or person, especially the intestines. When hunters dress a deer after hunting it, they remove the entrails. In ancient times, some cultures believed they could predict the future by examining the entrails of sacrificed animals.
The word appears frequently in classic adventure stories and historical accounts. When a ship's surgeon in a naval tale describes a sailor's wound as exposing his entrails, he means the injury was severe enough to reveal internal organs.
It almost always refers to organs that have been removed or exposed. You wouldn't use it to talk about healthy organs inside a living body working normally. Instead, it describes organs in contexts like butchering meat, historical medical procedures, or ancient religious practices.
The word has a visceral, somewhat unpleasant quality to it. While intestines is the neutral medical term, entrails carries more dramatic weight. A biology textbook describes intestines; a medieval chronicle describes entrails. This makes it perfect for historical fiction but less common in everyday conversation, where people prefer more clinical terms like organs or guts.