Cognomen Mordehay (מרדכי 
, Mordehay 
, مردخاي 
) , worldwide, is quite a rare surname. The family name Mordehay is habitual in Israel, where it is quite a common surname, Russia, where it is a very rare surname, and Canada, where it is an extremely rare surname. Not in comparison with a country's population, it is the most numerous in Israel, Russia, and Mexico. More frequently, Mordehay is the forename as well as the last name.