A system of tribute in the Trobriand Islands (in Papua New Guinea). It is practiced between brothers-in-law. A man is obligated by tradition to give some of the food he grows to his sister's husband. A man who is married and has a married sister will give a percentage of his garden's produce to his sister's husband, and receive produce from his wife's brother. Chiefs, who are polygamous, receive quite a bit of tribute under this system.

"Urigubu", apparently, means "maintenance".

Sources:
http://www.anthro.ucdavis.edu/courses/f02/ant2/AN2LEC9.htm