Its meaning differs based on the Hanja used to write it.
As a family name, Moon is written with one hanja, meaning "writing" (文; 글월 문 geulwol mun).
The 2000 South Korean census found a total of 426,927 people and 132,881 households with this family name.
They identified with 47 different surviving bon-gwan (origin of a clan lineage, not necessarily the actual residence of the clan members):[1] In a study by the National Institute of the Korean Language based on 2007 application data for South Korean passports, it was found that 73.5% of people with this surname spelled it in Latin letters as Moon in their passports, while another 26.4% spelled it as Mun.
[3] There are 14 Hanja with the reading Moon on the South Korean government's official list of hanja which may be registered for use in given names; they are:[4] People with the single-syllable given name Moon include: Korean names containing the element Moon include: