Family name 兰丁 (兰丁 
, Lambdin 
) , across the world, is quite a rare last name. The cognomen 兰丁 is characteristic of the United States, where it is a rare surname, New Zealand, and Canada, where it is a very rare surname. Measured by absolute frequency, it is the most numerous in the United States, the United Kingdom, and Canada. Much less frequently, 兰丁 is the forename as well as the last name.