Origin: Latin suffix -al
Intestinal has 3 different meanings across 1 category:
Relating to the intestines.
"The intestinal tract is located entirely within the body cavity, making it an internal organ system."
Internal.
In plain English: Intestinal means relating to your intestines, which are the long tubes inside your belly where food gets digested and nutrients get absorbed into your body.
"The doctor prescribed medication to treat his intestinal problems after he ate spoiled food."
From Latin intestīnālis. By surface analysis, intestine + -al.