Orchitis is a medical condition that affects the testicles, causing inflammation and pain. There are several synonyms for orchitis, including testicular inflammation, testis inflammation, and testicular swelling. Other related terms include epididymitis, which is inflammation of the epididymis, and hydrocele, which is an accumulation of fluid in the scrotum. Common symptoms of orchitis and its synonyms include pain or discomfort in the scrotum, swelling, and fever. Orchitis can be caused by a bacterial infection, viral infection, or injury. Treatment typically involves antibiotics, pain management, and rest. If left untreated, orchitis can lead to complications, including infertility.