It is a girl name if it is spelled sydney if it is spelled Sidney then it's a boy name.
It's a unisex name, meaning it could be either. Just like the name Alex...it could be short for the girl name Alexandra or the male name Alexander.
Jim's full name in the gift of magi was James Dillingham Young
full of life
Edith Franks full name was Edith Hollander Frank. Although she preferred Edith Frank, her real name by law was Edith Hollander Frank.
It is John Sidney McCain III.
John Sidney McCain 111 John Sidney McCain III (3rd)
Arizona senator and Republican presidential candidate's full name is John Sidney McCain III. His oldest biological son is John Sidney McCain IV.
Sidney Carlyle's birth name is Sidney D. Carlyle.
Sidney Moncrief's birth name is Sidney A. Moncrief.
Sidney Magal's birth name is Magalhes, Sidney.
Sidney Marion's birth name is Sidney Marienberg.
Sidney Sheldon's birth name is Sidney Schechtel.
Sidney Catlett's birth name is Sidney Catlett.
Sidney Torch's birth name is Sidney Torchinsky.
Sidney Kingsley's birth name is Sidney Kirshner.
Sidney Arodin's birth name is Sidney Arnondrin.