Caudal block is a type of regional anesthesia used for pain control during lower abdominal surgery, labor, or delivery. However, there are many synonyms for this term which include sacral epidural block, sacral block, posterior epidural block, and lumbosacral epidural block. These terms all refer to the same procedure, where the anesthesia is injected into the epidural space around the sacrum or lower back. Other related terms include spinal anesthesia, epidural anesthesia, and regional anesthesia. It's important to be familiar with these terms so that patients and healthcare providers can communicate effectively and provide optimal pain relief during surgery or labor.