Tomodachi Life. It is randomly generated (other than the island name), and its purpose is to give the Island a unique and recognizable name, as two islands can be given the same island name. Travelers received though StreetPass will state the name of their original Island. Clothes and hats received through StreetPass and/or SpotPass will display the name of the Island they came from (usually Nintendo Island in Spotpass) and will be able for purchase in Import Wear.
The Island Address consists of the island name, a 5 or 6 digit number code, an Isle name, and an Ocean name. Isle and Ocean names will always use the name of a food item.
Here is an example: