Rainier is a distinctive boys' name in United States, ranking #5748 in 1998 with 11 recorded births. The name reached its all-time peak in 2023 with 41 births ranking #3045. Since 1996, the popularity has increased by 22.2%. In 1998, approximately 1 in every 173,756 boys born was named Rainier. FALLING Recent data shows the name is currently falling.