The term 'semicircular area' can be abbreviated to APSE, which is a four-letter word. An APSE is an architectural feature that is typically found in churches and other religious buildings. It is a curved wall that is usually located at the end of the building, behind the altar or main seating area. The APSE is often used to house the choir or other musical instruments, and it is also used to create a sense of grandeur and awe.