Hilarius

Hilarius comes from the Latin hilaris, cheerful, the root that English keeps in hilarity. The fourth-century bishop of Poitiers, a theological combatant who defended Nicene orthodoxy in Gaul, carried the name into the saints' calendars and gave English its Hilary — first a man's name, later mostly a woman's. The original Latin form has stayed in ecclesiastical records and the occasional continental family. Four syllables, hi-LAH-ree-us, with a bright crest in the middle. The name carries a theological joke built in, a saint's name that simply means bright-spirited. It suits a boy with a quick laugh and the patience to argue a fine point of doctrine to its end.