Maël
Mael is an old Celtic name from Ireland, Wales and Brittany. Nowadays this first name is popular in France. 

The French masculine name of Breton origin meaning "chief, prince." It was popularized by a fifth-century saint Maël who lived in Wales.

It was also borne by Máel Sechnaill mac Domnaill (975/976-1022), a High King of Ireland.

Both a boys name and a girls name, although it seems traditionally more used on boys.
Its feminine form in Breton is Maela, but the modern French variant Maëlle is often preferred. In Welsh it is considered masculine.

In Wales, Mael is the legendary name of Roycol's son.

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