Regional ileitis, also known as Crohn's disease, is a type of inflammatory bowel disease that affects the small intestine and causes abdominal pain, diarrhea, and weight loss. There are several synonyms for the term regional ileitis that are commonly used in medical literature. Some of these synonyms include granulomatous colitis, ileocolitis, enteritis, and terminal ileitis. These terms are often used interchangeably with regional ileitis to describe the same condition. It is important for healthcare professionals and individuals with Crohn's disease to understand these synonyms to ensure effective communication and treatment. Treatment options include medication, surgery, and lifestyle changes.