Kieran’s name day is September 9, the feast of Ciaran of Clonmacnoise.
Churches that follow the Old (Julian) Calendar keep the same feast on September 22 of the civil calendar. See everything commemorated on September 9.
The saint behind the name
Ciaran of Clonmacnoise
September 9, Venerable, Κιαράν
St. Ciaran was born in Connacht in the early sixth century and studied under St. Finnian of Clonard, being counted among the twelve apostles of Ireland. He founded the monastery of Clonmacnoise on the Shannon, which became one of the great centers of learning of the Irish Church.
Also celebrating on September 9
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.