Rainier is a distinctive boys' name in United States, ranking #3500 in 2018 with 32 recorded births. The name reached its all-time peak in 2023 with 41 births ranking #3045. Since 1996, the popularity has increased by 255.6%. In 2018, approximately 1 in every 56,734 boys born was named Rainier. FALLING Recent data shows the name is currently falling.