Fontanalia, in antiquity, a religious feast held among the Romans in honour of the deities who presided over fountains or springs. Varro observes, that it was the custom to visit the wells on those days, and to cast crowns into fountains. Scaliger, in his conjectures on Varro, takes this not to be a feast of fountains in general, as Feltus intimates, but of the fountain which had a temple at Rome, near the Porta Capena, called also Porta Fontinalis: he adds, that it is of this fountain Cicero speaks in his second book De Legibus. The fontinalia were held on the 13th of October.

Fontinalis, water-moss, a genus of plants belonging to the cryptogamia class, and to the order of mucil. See Botany Index.