Literally translated means ‘many years’ the greeting given on name days. In Greece and Cyprus a name day is celebrated in a similar way to a birthday, each Saints name having a specific day in the calendar (today being Babis). In the case of Yannis (John) there are actually 4 name days and the individual would celebrate on the name day closest to his birth date. All well wishers are welcome on name days, guests are not invited as such but simply turn up to wish that person well. Gifts are brought and entertainment is provided by the host in the form of a meal, music, drinks.
When naming a newborn traditionally children are named after their grandparents meaning the continuation of names in the family line, their name is generally given at their baptism which some-times takes place many years after they are born.
Seeing as there is a Saints name pretty much every day it almost feels like a constant celebration, do see http://www.namedays.gr/index_uk.php