Rainier is a distinctive boys' name in United States, ranking #9662 in 2009 with 8 recorded births. The name reached its all-time peak in 2023 with 41 births ranking #3045. Since 1996, the popularity has decreased by 11.1%. In 2009, approximately 1 in every 247,913 boys born was named Rainier. FALLING Recent data shows the name is currently falling.