The surname Giordani is a form derived from the personal name Giordano, one of the most widespread names of biblical origin in Italy. It is a patronymic variant, in which the ending in -i can be read as "the sons of" or "the family of", so that Giordani means, in essence, "descendants of Giordano". This name has its origin in the Hebrew Yardén, by way of the Greek Iordanés and the Latin Iordanus, and goes back to the river Jordan, a central place in the Christian tradition on account of the baptism of Jesus. Its wide diffusion in the Middle Ages explains the great number of surnames generated from it, with multiple regional variants.

For a fuller account of the origin, meaning and history of this group of surnames —including its variants, its spread in Italy and its evolution over time— see the main entry devoted to the surname Giordano, where the subject is developed more extensively.