Sydney is a spelling of Sidney, an English surname that probably comes from a place name meaning "wide island" or "wide meadow", from the Old English sidan and eg; the Australian city was named after Lord Sydney in 1788. It became a top girls' name in America in the 1990s, part of the fashion for surnames and place names. Sydney ranked number 23 in the United States in 2000, its peak this century, and has gradually declined to number 348 in 2025.