Lionel is one leonine name that hasn't taken off as cousins Leo and Leonardo have, though it did reenter the Top 1000 in 2010 after several years away; it was at its highest point in the 1920s and 1930s.

This French diminutive of Leon has had many worthy namesakes over time, including Sir Lionel, a Knight of the Round Table, actor Barrymore, critic Trilling, musicians Hampton and Richie, Argentine Olympic footballer Messi, and characters in numerous movies and TV shows--the real life speech therapist Lionel Logue was portrayed in The King's Therapist.

Lionel Barrymore, of the famed theatrical family, was a mainstay of Golden Age Hollywood films, and kids might like the association to Lionel trains.

This is a timeless choice worth considering.