Rainier is a distinctive boys' name in United States, ranking #3091 in 2022 with 40 recorded births. The name reached its all-time peak in 2023 with 41 births ranking #3045. Since 1996, the popularity has increased by 344.4%. In 2022, approximately 1 in every 43,609 boys born was named Rainier. FALLING Recent data shows the name is currently falling.