Plato’s name day is November 18, the feast of Plato of Ancyra.
Churches that follow the Old (Julian) Calendar keep the same feast on December 1 of the civil calendar. See everything commemorated on November 18.
The saint behind the name
Plato of Ancyra
November 18, Martyr, Πλάτων
The holy martyr Plato was a young Christian of Ancyra in Galatia who suffered in the persecutions at the beginning of the fourth century. Brought before the governor, he refused every inducement to deny Christ, answered his judges with boldness and wisdom, and after enduring cruel tortures was beheaded.
Also celebrating on November 18
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.