Rainier is a distinctive boys' name in United States, ranking #5471 in 2006 with 16 recorded births. The name reached its all-time peak in 2023 with 41 births ranking #3045. Since 1996, the popularity has increased by 77.8%. In 2006, approximately 1 in every 128,445 boys born was named Rainier. FALLING Recent data shows the name is currently falling.