Synovial sheath is an anatomical term used to describe a protective layer that surrounds certain tendons in the body, helping them to move smoothly and reducing friction. This structure is also referred to as a synovial membrane or synovium. Other synonyms for synovial sheath include synovial bursa, tendon sheath, and fibrous sheath. These terms are often used interchangeably to describe the same structure, which is found in various locations throughout the body, including the hands, feet, and joints. Understanding the terminology used to describe anatomical structures is important for healthcare professionals and patients alike, as it can aid in communication and facilitate accurate diagnosis and treatment.