conjoined

Conjoined is an adjective meaning physically joined to another object or person. It derives from con- “together” and join, from the Latin iungere. In common usage, it most often refers to individuals whose bodies are connected at birth, a condition commonly described as conjoined twins.

Conjoined twins arise when a single fertilized egg splits incompletely during early development, producing two individuals who remain partially fused. The site and extent of the connection vary widely. Common categories include thoracopagus (joined at the chest), omphalopagus (upper abdomen), craniopagus (head), and pygopagus (lower spine or sacral region). In some cases twins share vital organs, while in others they share skin and tissue but have separate organs. Separation surgery may be considered when feasible, but outcomes depend on anatomy and shared systems; some separations are successful, others are not possible.

Diagnosis is often made before birth through ultrasound and fetal MRI, with postnatal assessment guiding treatment decisions. Prenatal counseling, multidisciplinary planning, and ethical considerations are integral to care. Prognosis varies and is closely tied to the extent of organ sharing and overall health.

Beyond people, the term conjoined can describe objects or structures that are physically joined, such as sculptures or architectural elements joined at a hinge or seam. The concept emphasizes a physical linkage between components rather than a separate, independent existence.