From the experts:
This lilting Irish saint's name shone in neon lights on Broadway for the classical 1947 musical "Finian's Rainbow," later made into a film starring Fred Astaire as Finian McLonergan, and there was also a character on
"General Hospital" named Finian O'Toole. With the growing popularity of Finn and Finlay/Finley--and boys' names ending in 'an'--Finian, which can also be spelled Finnian, seems like a sure-fire winner.
One of several early St. Finnians was a noted teacher and scholar.