English form of Eustachius, a Latin form of the Greek name Ευσταχυς (Eustachys) meaning "fruitful". Saint Eustace was a 2nd-century martyr, a Roman general who became a Christian after seeing a vision of a cross between the antlers of a stag he was hunting. He was burned to death for refusing to worship the Roman gods and is now regarded as the patron saint of hunters. Due to him, this name was common in England during the Middle Ages, though it is presently rare.