Sydnei is a distinctive girls' name in United States, ranking #4009 in 1998 with 29 recorded births. The name reached its all-time peak in 2005 with 37 births ranking #3936. Since 1996, the popularity has decreased by 14.7%. In 1998, approximately 1 in every 60,927 girls born was named Sydnei. RISING Recent data shows the name is currently rising.