Ahn, also romanized An, is a common Korean family name. It literally means "tranquil." In 2000, there were 637,786 people bearing this surname in South Koreahttp://kosis.nso.go.kr/cgi-bin/sws_999.cgi?ID=DT_1INOOSB&IDTYPE=3, making it the 20th most common family name in the country, with roughly 2% of the country's population.