Galaktion’s name day is November 5, the feast of Galaktion and Episteme.
Churches that follow the Old (Julian) Calendar keep the same feast on November 18 of the civil calendar. See everything commemorated on November 5.
The saint behind the name

Galaktion and Episteme
November 5, Martyr, Γαλακτίων και Επιστήμη
Saints Galaktion and Episteme were a young married couple of Emesa in Syria who, according to tradition, agreed to preserve chastity and gave themselves to the ascetic life, each entering a monastic community. When persecution arose, Galaktion was seized for his faith, and Episteme freely joined him in confessing Christ; together they endured torture and were put to death.
Name days: Galaktionas, Galaktion
Also celebrating on November 5
These names share the feast, many of them other forms of the same name:
What to say on a name day
The Greek wish is Χρόνια Πολλά (Chronia Polla), “many years.” A call or a short message on the day is what people remember. See name day wishes you can send and what a name day is.