Issy

From the Greek name Ισιδωρος (Isidoros) which meant "gift of Isis", derived from the name of the Egyptian goddess ISIS combined with Greek δωρον (doron) "gift". Saint Isidore of Seville was a 6th-century archbishop, historian and theologian.

Though it has never been popular in the English-speaking world among Christians, it has historically been a common name for Jews, who have used it as an Americanized form of names such as Isaac, Israel and Isaiah.

Greek form of Egyptian Ist (reconstructed as Iset or Ueset), which possibly meant "the throne". In Egyptian mythology Isis was the goddess of the sky and nature, the wife of Osiris and the mother of Horus. She was originally depicted wearing a throne-shaped headdress, but in later times she was conflated with the goddess Hathor and depicted having the horns of a cow on her head. She was also worshipped by people outside of Egypt, such as the Greeks and Romans.

Latinate form of ISABEL. This name was borne by many medieval royals, including queen consorts of England, France, Portugal, the Holy Roman Empire and Hungary, as well as the powerful ruling queen Isabella of Castile (properly called Isabel).

Medieval Occitan form of ELIZABETH. It spread throughout Spain, Portugal and France, becoming common among the royalty by the 12th century. It grew popular in England in the 13th century after Isabella of Angoulême married the English king John, and it was subsequently bolstered when Isabella of France married Edward II the following century.

This is the usual form of the name Elizabeth in Spain and Portugal, though elsewhere it is considered a parallel name, such as in France where it is used alongside Élisabeth. The name was borne by two Spanish ruling queens, including Isabel of Castile, who sponsored the explorations of Christopher Columbus.

From Ελισαβετ (Elisabet), the Greek form of the Hebrew name אֱלִישֶׁבַע ('Elisheva') meaning "my God is an oath" or perhaps "my God is abundance". The Hebrew form appears in the Old Testament where Elisheba is the wife of Aaron, while the Greek form appears in the New Testament where Elizabeth is the mother of John the Baptist.

Among Christians, this name was originally more common in Eastern Europe. It was borne in the 12th century by Saint Elizabeth of Hungary, a daughter of King Andrew II who used her wealth to help the poor. In medieval England it was occasionally used in honour of the saint, though the form Isabel (from Occitan and Spanish) was more common. It has been very popular in England since the reign of Queen Elizabeth I in the 16th century. It has also been borne (in various spellings) by many other European royals, including a ruling empress of Russia in the 18th century. Famous modern bearers include the British queen Elizabeth II (1926-) and actress Elizabeth Taylor (1932-2011).