Phineas

Julia Roberts drew the biblical Phineas into the limelight when she chose it, with the even-more-antique spelling Phinnaeus, for her twin son, now called Finn. Phineas had last been heard from via circus impresario Phineas T. Barnum, until it was brought somewhat up to date via the Disney Channel animated show Phineas and Ferb.

Anthony Trollope combined name and nickname for the young, handsome and charming Irish lawyer hero of his eponymous novel, Phineas Finn. Phineas is also the name of three biblical personages and was popular among the seventeenth century Puritans. Jazz pianist Phineas Newborn, Jr. is a contemporary namesake.

Trivia note: In early movies, characters named Phineas had nicknames like Prune, Whipsnake and Whoopee.

Bottom line: A quirky path to nickname Finn.