For a long time, Isadora has been overlooked in favor of Isabella, owing perhaps to its association with the tragic modern dancer, Isadora Duncan, or because parents would rather their daughter be a Bella than a Dora. Now, with Theodora back in the charts and vintage names in vogue, Isadora has been slowly gaining more attention over the last decade.

Isabel, Theodore, and Isadora are back: could it now be time for a more widespread revival of Isidore? Yet to see any big moves up the charts, Isidore was given to more than 30 boys in a recent year: twice the number it was given to a decade ago.

A classic variation of the name Isidore, both Isadore and Isidore were equally popular at their peak in the 1910s. They were historically used among Jewish families — Isidore and Isadore were often used as Americanizations of Jewish names such as Israel and Isaac.

The Isidora spelling, though equally legitimate, is about 90 percent less common than Isadora.

Isidore and variants are remarkably underused and ripe for revival, a la Theodore and company.

Another Spanish boys' name that relates to a goddess, the Egyptian Isis. San Isidro is the patron saint of Madrid.

Izya is a unisex Russian nickname, used for Isaak and Isidore for boys, and for Isabel and Isidora for girls. Unlike other Russian nicknames (Sasha, Anya, Sonya), this has not caught on internationally yet.