The adjective internal refers to something that exists or occurs inside another thing or being.
Inside the body.
Example: Internal organs such as the heart and lungs.
Inside a person's mind or emotions.
Example: She experienced internal conflict about her decision.
Inside an object, building, or system.
Example: The building’s internal structure was redesigned.
The term is often contrasted with external, which refers to what lies outside. It applies broadly to anatomy, psychology, architecture, and technical systems.
“Internal” emphasizes processes or locations within a defined boundary — physical, emotional, or structural.
Author’s summary: The word “internal” describes anything located or happening inside a body, mind, object, or structure, highlighting inward position or process.