Cognomen Rajjak (Rajjak 
) , around the world, is a common last name. The surname Rajjak is habitual in Western Asia, particularly Oman, where it is quite a rare surname, Saudi Arabia, and Qatar. Not in comparison with a country's population, this name is the most popular in India, Bangladesh, and Saudi Arabia. Also, Rajjak is the forename as well as the last name.