I Hate Top Ten's Personal Name List

Anglicized form of Irish Deaglán, Old Irish Declán, which is of unknown meaning. Saint Declan was a 5th-century missionary to the Déisi peoples of Ireland and the founder of the monastery at Ardmore.

In America, this name received boosts in popularity from main characters in the movies The Jackal (1997) and Leap Year (2010).

Anglicized form of Ciarán.

Derived from Old Irish finn "white, blessed". This was the name of several Irish saints, including the founders of monasteries at Clonard and Movilla (both 6th century).

From Brendanus, the Latinized form of the Old Irish name Bréanainn, which was derived from Old Welsh breenhin meaning "king, prince". Saint Brendan was a 6th-century Irish abbot who, according to legend, crossed the Atlantic and reached North America with 17 other monks.