Siobhan is a distinctive girls' name in United States, ranking #1993 in 2001 with 86 recorded births. The name reached its all-time peak in 1997 with 139 births ranking #1272. Since 1996, the popularity has decreased by 37.7%. In 2001, approximately 1 in every 20,937 girls born was named Siobhan. FALLING Recent data shows the name is currently falling.