Gender masculine Κωστάκης is a diminutive form of Greek name Κώστας.Feasts and saints related to given name Κωστάκης Sts Constantin le Grand et sa mère Hélène, égaux des Apôtres Feast day May 21 When is Κωστάκης's name day? Κωστάκης's Day is celebrated on May 21 in memory of Sts Constantin le Grand et sa mère Hélène. Name form diminutive Transcriptions Kostakis(la) Log in or register to post comments Be the first to rate this name Leave this field blank