I may not be Daividh, but I think I can do in a pinch.
The name probably comes from the Finnean Cycle, which were the exploits of Fionn mac Chuill, his sons and his warriors. It is one of the two most famous pieces of Celtic "literature" (since their culture was more an oral culture than a written one). The other is the Ulster Cycle featuring the hero Cuchullin (I think that's how it's spelled). I'm grateful my Gaelic professor hasn't signed on to this board yet, or I'd REALLY be in trouble (I've had him for seven semesters and we keep in touch on campus). [ :P]