Alexei is a Russian variant of Alexander. The name Alexander is a general European name, derived from the Old Greek name 'Alexandros', itself derived from the words 'alexein', which means 'to ward off or to defend', and 'andros or aner', which means 'man'. It means defender, helper, guardian of people. In other words, it is a name which signifies strength or protection. It was the name given to one of the greatest kings on Earth, Alexander The Great.