ankylosing spondylitis: a chronic form of spondylitis primarily in males and marked by impaired mobility of the spine; sometimes leads to ankylosis
autoimmune disease: any of a large group of diseases characterized by abnormal functioning of the immune system that causes your immune system to produce antibodies against your own tissues
sandarac: durable fragrant wood; used in building (as in the roof of the cathedral at Cordova, Spain)