The South Korean government, as written in hanja on the wooden structure, officially calls the landmark Sungnyemun (English: Gate of Exalted Ceremonies), even though it has been more commonly known as Namdaemun (English: Great Southern Gate) since the Joseon dynasty. Most of people are thinking the name “Namdaemun” was changed forcibly by the Japanese Empire(colonial period ) and arguing that it should not be used. However, by following the annals of the Joseon Dynasty, naming and calling the 8 gates with the direction were slang terms. Thus, even they were slang, they’ve never been vestiges of the Japanese Colonial era.
Different from the other gates, Sungnyemun's tablet has its name written vertically. When the first king of the Joseon dynasty, Yi Seonggye (reign 1335-1408), constructed the capital city, he believed that fire would reach to Gyeongbokgung Palace, as well as to the capital city, as Mt. Gwanaksan of Seoul is shaped like fire according to feng shui principles. Sungnyemun's name means "fire", which is from the harmony of the Five Elements and, if written vertically, the Chinese character "fire" looks as if it is providing protection. This was Taejong's (1367–1422) first son, Yangnyeongdaegun's (1394-1462), famous writing.