Sidney is a distinctive girls' name in United States, ranking #1878 in 2025 with 105 recorded births. The name reached its all-time peak in 2000 with 1,221 births ranking #265. Since 1996, the popularity has decreased by 87.3%. In 2025, approximately 1 in every 15,307 girls born was named Sidney. FALLING Recent data shows the name is currently falling.
Sidney is an English surname name that later moved into first-name use. Its modern identity comes more from that surname history than from a single neat word meaning.
Behind the Name says it first became a given name in honour of Algernon Sidney, and later usage was shaped by other notable bearers of the surname. In the United States it also shifted across gender lines over time.