Rainier is a distinctive boys' name in United States, ranking #6711 in 2000 with 10 recorded births. The name reached its all-time peak in 2023 with 41 births ranking #3045. Since 1996, the popularity has increased by 11.1%. In 2000, approximately 1 in every 196,393 boys born was named Rainier. FALLING Recent data shows the name is currently falling.