Costovertebral angle tenderness is a medical condition that refers to pain or discomfort in the area where the ribs attach to the spine. There are several synonyms used in the medical field to describe this condition, including flank tenderness, kidney tenderness, and renal angle tenderness. Additionally, terms such as lumbar tenderness and low back pain can also be used to describe this type of discomfort. Some people may also experience pain in the costovertebral junction or the costo-iliac area, which can be described using terms such as triangular vertebral region tenderness or sacroiliac tenderness. These synonyms can help medical professionals diagnose and treat patients experiencing pain in these areas.