Cognomen 吉兰 (Jilan 
, 吉兰 , Gillan 
) , in all the world, is quite a common surname. The last name 吉兰 is characteristic of Ireland, where it is quite a rare surname, the United Kingdom, and New Zealand. Not in comparison with a country's population, the name is most common in the United Kingdom, the United States, and China. Also, 吉兰 is the forename as well as the last name.