Isidora is the feminine of isidoro, coming from the ancient Greece where already after fallen name the Egyptian Empire was still worshipping the goddess Isis, the gift of isis was the fertility and the Earth. Isidora is therefore the "gift of isis", Goddess of the fertiluza, the prosperity of harvests.
Name of woman, not very common, in Spain. It has a Greek etymology: Isis Isidos: Isis, Egyptian goddess and doron dorou: don, offering: offerings to Isis. This goddess was the sister and wife of Osiris ( for the gods there was no prohibition of incest ) and his cult spread after the conquest of Egypt by Rome through the Mediterranean and even the British Isles. The Romans associated with the Phrygian Cybele and Ceres.