Rainier is a distinctive boys' name in United States, ranking #3976 in 2012 with 26 recorded births. The name reached its all-time peak in 2023 with 41 births ranking #3045. Since 1996, the popularity has increased by 188.9%. In 2012, approximately 1 in every 72,947 boys born was named Rainier. FALLING Recent data shows the name is currently falling.