As a boy's name this is a pet form of Jeremy or Gerald, or occasionally of Gerard and Jerome. As a girl's name it is a variant spelling of Gerry, and is sometimes bestowed as an independent given name, as in the case of the American model and actress Jerry Hall (b. 1956).
Italian: from stella ‘star’. In most cases it probably derives from a medieval female personal name or nickname, but it may also have been a habitational name for someone who lived at a house distinguished by the sign of a star or from any of the places so named (for example in Savona and Salerno), or a topographic name for someone who lived at a place from which roads radiated out in various different directions.