Last name Lavai (Lavai 
) , in all the world, is a rare family name. The cognomen Lavai is habitual in Papua New Guinea, where it is quite a rare surname, the United Kingdom, where it is an extremely rare surname, and France. Measured by absolute frequency, this name is the most popular in Papua New Guinea, India, and the United Kingdom. Very seldom, Lavai is the forename as well as the last name.