Surname Gagay (Gagay 
, Гагай 
) , in the world, is a rare family name. The cognomen Gagay is habitual in Eastern Europe, particularly Russia, where it is a rare surname, Belarus, and Ukraine, where it is a very rare surname. Not in comparison with a country's population, it is the most numerous in Russia, India, and Ukraine. Much less frequently, Gagay is the forename as well as the last name.